From fdf1782069b4f8141e3d4d431dac0f82621d8b07 Mon Sep 17 00:00:00 2001
From: copygirl <copygirl@mcft.net>
Date: Mon, 3 May 2021 17:26:03 +0200
Subject: [PATCH] Add Saving / Loading support

- Add SaveRegistry and SaveAttribute
- Add Save, which handles Saving / Loading
- Add SpawnRegistry and SpawnAttribute
  Allows spawning objects by ID or Type
- PropertyDeSerializer handles de/serialization
  of any [Sync] and [Save] properties
- Removing objects now done by
  removing it from the scene tree
- Add "World" tab to EscapeMenu
- Modify Heartbit font's 1 and V characters
---
 CREDITS.md                      |   4 +-
 HeartbitXX.ttf                  | Bin 40248 -> 40280 bytes
 project.godot                   |   2 +
 scene/EscapeMenu.tscn           | 227 ++++++++++++++++++++++++++++----
 src/CreativeBuilding.cs         |   4 +-
 src/EscapeMenu.cs               |   2 +-
 src/EscapeMenuMultiplayer.cs    |   8 +-
 src/EscapeMenuWorld.cs          | 133 +++++++++++++++++++
 src/IO/DeSerializer.Impl.cs     |  31 +++--
 src/IO/DeSerializerRegistry.cs  |   8 +-
 src/IO/PropertyDeSerializer.cs  |  48 +++++++
 src/IO/Save.cs                  | 100 +++++++++++++-
 src/IO/SaveRegistry.cs          |  69 ++++++++++
 src/Network/IntegratedServer.cs |   6 +-
 src/Network/Sync.cs             |  66 +++++++---
 src/Network/SyncClient.cs       |  22 +---
 src/Network/SyncRegistry.cs     |  85 ++++--------
 src/Network/SyncServer.cs       |  54 +++-----
 src/Objects/Block.cs            |   6 +-
 src/Objects/ObjectHolder.cs     |  58 +++++---
 src/Objects/Player.cs           |   4 +-
 src/Objects/SpawnRegistry.cs    |  70 ++++++++++
 src/Scenes/Game.cs              |   7 +-
 src/Scenes/Server.cs            |   7 +-
 src/Utility/Extensions.cs       |  36 ++++-
 ui_theme.tres                   |   2 +-
 26 files changed, 837 insertions(+), 222 deletions(-)
 create mode 100644 src/EscapeMenuWorld.cs
 create mode 100644 src/IO/PropertyDeSerializer.cs
 create mode 100644 src/IO/SaveRegistry.cs
 create mode 100644 src/Objects/SpawnRegistry.cs

diff --git a/CREDITS.md b/CREDITS.md
index 9feccdf..7a8529b 100644
--- a/CREDITS.md
+++ b/CREDITS.md
@@ -5,5 +5,7 @@
 **URL:** https://arcade.itch.io/heartbit  
 **Author:** Void  
 **License:** Custom  
-> You can use this font in free and personal projects, works or games.
+> You can use this font in free and personal projects, works or games.  
 > You'll need to pay the suggested price for commercial projects.
+
+**Notes:** Modified `1` and `V` characters.
diff --git a/HeartbitXX.ttf b/HeartbitXX.ttf
index 71ff9adccec13c50d3cf60a6b393bc79448de771..a3dfd696be9d81eb547bec7cdb660611509048bd 100644
GIT binary patch
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diff --git a/project.godot b/project.godot
index 6d3a700..e4e204e 100644
--- a/project.godot
+++ b/project.godot
@@ -16,6 +16,8 @@ _global_script_class_icons={
 
 config/name="YourFortV"
 run/main_scene="res://scene/ClientScene.tscn"
+config/use_custom_user_dir=true
+config/custom_user_dir_name="YourFortV"
 boot_splash/image="res://gfx/icon.png"
 boot_splash/use_filter=false
 config/icon="res://gfx/icon.png"
diff --git a/scene/EscapeMenu.tscn b/scene/EscapeMenu.tscn
index 52c0a92..dbd21a2 100644
--- a/scene/EscapeMenu.tscn
+++ b/scene/EscapeMenu.tscn
@@ -1,10 +1,11 @@
-[gd_scene load_steps=6 format=2]
+[gd_scene load_steps=7 format=2]
 
 [ext_resource path="res://ui_theme.tres" type="Theme" id=1]
 [ext_resource path="res://src/EscapeMenu.cs" type="Script" id=2]
 [ext_resource path="res://gfx/player.png" type="Texture" id=3]
 [ext_resource path="res://src/EscapeMenuMultiplayer.cs" type="Script" id=4]
 [ext_resource path="res://src/EscapeMenuAppearance.cs" type="Script" id=5]
+[ext_resource path="res://src/EscapeMenuWorld.cs" type="Script" id=6]
 
 [node name="EscapeMenu" type="Control"]
 anchor_right = 1.0
@@ -25,6 +26,47 @@ __meta__ = {
 "_edit_lock_": true
 }
 
+[node name="SaveFileDialog" type="FileDialog" parent="."]
+anchor_left = 0.5
+anchor_top = 0.5
+anchor_right = 0.5
+anchor_bottom = 0.5
+margin_left = -240.0
+margin_top = -160.0
+margin_right = 240.0
+margin_bottom = 160.0
+rect_min_size = Vector2( 0, 0 )
+window_title = "Save World As..."
+mode_overrides_title = false
+access = 2
+filters = PoolStringArray( "*.yf5 ; YourFortV Save" )
+current_dir = "/"
+current_path = "/"
+__meta__ = {
+"_edit_use_anchors_": false
+}
+
+[node name="LoadFileDialog" type="FileDialog" parent="."]
+anchor_left = 0.5
+anchor_top = 0.5
+anchor_right = 0.5
+anchor_bottom = 0.5
+margin_left = -240.0
+margin_top = -160.0
+margin_right = 240.0
+margin_bottom = 160.0
+rect_min_size = Vector2( 0, 0 )
+window_title = "Load World From..."
+mode_overrides_title = false
+mode = 0
+access = 2
+filters = PoolStringArray( "*.yf5 ; YourFortV Save" )
+current_dir = "/"
+current_path = "/"
+__meta__ = {
+"_edit_use_anchors_": false
+}
+
 [node name="CenterContainer" type="CenterContainer" parent="."]
 anchor_right = 1.0
 anchor_bottom = 1.0
@@ -66,8 +108,7 @@ margin_bottom = 17.0
 margin_top = 21.0
 margin_right = 229.0
 margin_bottom = 139.0
-custom_constants/side_margin = 4
-tab_align = 0
+custom_constants/side_margin = 0
 use_hidden_tabs_for_min_size = true
 
 [node name="Appearance" type="CenterContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer"]
@@ -148,7 +189,7 @@ text = "(Close Menu to apply changes.)"
 align = 1
 valign = 2
 
-[node name="Multiplayer" type="VBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer"]
+[node name="Multiplayer" type="CenterContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer"]
 visible = false
 anchor_right = 1.0
 anchor_bottom = 1.0
@@ -157,20 +198,24 @@ margin_top = 27.0
 margin_right = -4.0
 margin_bottom = -4.0
 script = ExtResource( 4 )
-StatusPath = NodePath("ContainerStatus/Status")
-ServerOpenClosePath = NodePath("ContainerServer/ServerOpenClose")
-ServerPortPath = NodePath("ContainerServer/ServerPort")
-ClientDisConnectPath = NodePath("ContainerClient/ClientDisConnect")
-ClientAddressPath = NodePath("ContainerClient/ClientAddress")
+StatusPath = NodePath("VBoxContainer/ContainerStatus/Status")
+ServerOpenClosePath = NodePath("VBoxContainer/ContainerServer/ServerOpenClose")
+ServerPortPath = NodePath("VBoxContainer/ContainerServer/ServerPort")
+ClientDisConnectPath = NodePath("VBoxContainer/ContainerClient/ClientDisConnect")
+ClientAddressPath = NodePath("VBoxContainer/ContainerClient/ClientAddress")
+
+[node name="VBoxContainer" type="VBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer"]
+margin_right = 221.0
+margin_bottom = 87.0
 
-[node name="ContainerStatus" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer"]
+[node name="ContainerStatus" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer"]
 margin_right = 221.0
 margin_bottom = 13.0
 __meta__ = {
 "_edit_use_anchors_": false
 }
 
-[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerStatus"]
+[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerStatus"]
 margin_top = 2.0
 margin_right = 36.0
 margin_bottom = 11.0
@@ -178,7 +223,7 @@ rect_min_size = Vector2( 36, 0 )
 text = "Status:"
 align = 2
 
-[node name="Status" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerStatus"]
+[node name="Status" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerStatus"]
 modulate = Color( 1, 0, 0, 1 )
 margin_left = 40.0
 margin_right = 221.0
@@ -193,12 +238,12 @@ __meta__ = {
 "_edit_use_anchors_": false
 }
 
-[node name="ContainerServer" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer"]
+[node name="ContainerServer" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer"]
 margin_top = 17.0
 margin_right = 221.0
 margin_bottom = 36.0
 
-[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerServer"]
+[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerServer"]
 margin_top = 5.0
 margin_right = 36.0
 margin_bottom = 14.0
@@ -206,7 +251,7 @@ rect_min_size = Vector2( 36, 0 )
 text = "Port:"
 align = 2
 
-[node name="ServerPort" type="LineEdit" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerServer"]
+[node name="ServerPort" type="LineEdit" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerServer"]
 margin_left = 40.0
 margin_right = 90.0
 margin_bottom = 19.0
@@ -218,7 +263,7 @@ __meta__ = {
 "_edit_use_anchors_": false
 }
 
-[node name="ServerOpenClose" type="Button" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerServer"]
+[node name="ServerOpenClose" type="Button" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerServer"]
 margin_left = 94.0
 margin_right = 221.0
 margin_bottom = 19.0
@@ -228,12 +273,12 @@ __meta__ = {
 "_edit_use_anchors_": false
 }
 
-[node name="ContainerClient" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer"]
+[node name="ContainerClient" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer"]
 margin_top = 40.0
 margin_right = 221.0
 margin_bottom = 59.0
 
-[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerClient"]
+[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerClient"]
 margin_top = 5.0
 margin_right = 36.0
 margin_bottom = 14.0
@@ -241,7 +286,7 @@ rect_min_size = Vector2( 36, 0 )
 text = "Address:"
 align = 2
 
-[node name="ClientAddress" type="LineEdit" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerClient"]
+[node name="ClientAddress" type="LineEdit" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerClient"]
 margin_left = 40.0
 margin_right = 160.0
 margin_bottom = 19.0
@@ -249,7 +294,7 @@ rect_min_size = Vector2( 120, 0 )
 align = 1
 caret_blink = true
 
-[node name="ClientDisConnect" type="Button" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerClient"]
+[node name="ClientDisConnect" type="Button" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerClient"]
 margin_left = 164.0
 margin_right = 221.0
 margin_bottom = 19.0
@@ -257,17 +302,17 @@ rect_min_size = Vector2( 57, 0 )
 size_flags_horizontal = 3
 text = "Connect"
 
-[node name="ContainerHideAddress" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer"]
+[node name="ContainerHideAddress" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer"]
 margin_top = 63.0
 margin_right = 221.0
 margin_bottom = 87.0
 
-[node name="HideAddress" type="CheckBox" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerHideAddress"]
+[node name="HideAddress" type="CheckBox" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerHideAddress"]
 margin_right = 82.0
 margin_bottom = 24.0
 text = "Hide Address"
 
-[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerHideAddress"]
+[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerHideAddress"]
 margin_left = 86.0
 margin_top = 7.0
 margin_right = 173.0
@@ -275,6 +320,129 @@ margin_bottom = 16.0
 custom_colors/font_color = Color( 0.6, 0.6, 0.6, 1 )
 text = "(for streamers etc.)"
 
+[node name="World" type="CenterContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer"]
+visible = false
+anchor_right = 1.0
+anchor_bottom = 1.0
+margin_left = 4.0
+margin_top = 27.0
+margin_right = -4.0
+margin_bottom = -4.0
+script = ExtResource( 6 )
+FilenamePath = NodePath("VBoxContainer/HBoxContainer/Filename")
+LastSavedPath = NodePath("VBoxContainer/HBoxContainer3/LastSaved")
+PlaytimePath = NodePath("VBoxContainer/HBoxContainer2/Playtime")
+QuickSavePath = NodePath("VBoxContainer/HBoxContainer4/QuickSave")
+SaveAsPath = NodePath("VBoxContainer/HBoxContainer4/SaveAs")
+SaveFileDialogPath = NodePath("../../../../../SaveFileDialog")
+LoadFileDialogPath = NodePath("../../../../../LoadFileDialog")
+
+[node name="VBoxContainer" type="VBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World"]
+margin_left = 20.0
+margin_top = 1.0
+margin_right = 200.0
+margin_bottom = 86.0
+rect_min_size = Vector2( 180, 0 )
+
+[node name="HBoxContainer" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer"]
+margin_right = 180.0
+margin_bottom = 9.0
+
+[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer"]
+margin_right = 58.0
+margin_bottom = 9.0
+rect_min_size = Vector2( 58, 0 )
+text = "Filename:"
+align = 2
+
+[node name="Filename" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer"]
+margin_left = 62.0
+margin_right = 180.0
+margin_bottom = 9.0
+size_flags_horizontal = 3
+custom_colors/font_color = Color( 0.6, 0.6, 0.6, 1 )
+text = "-not saved yet-"
+align = 1
+
+[node name="HBoxContainer2" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer"]
+margin_top = 13.0
+margin_right = 180.0
+margin_bottom = 22.0
+
+[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer2"]
+margin_right = 58.0
+margin_bottom = 9.0
+rect_min_size = Vector2( 58, 0 )
+text = "Playtime:"
+align = 2
+
+[node name="Playtime" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer2"]
+margin_left = 62.0
+margin_right = 180.0
+margin_bottom = 9.0
+size_flags_horizontal = 3
+custom_colors/font_color = Color( 0.6, 0.6, 0.6, 1 )
+text = "000d 00h 00m 00s"
+align = 1
+
+[node name="HBoxContainer3" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer"]
+margin_top = 26.0
+margin_right = 180.0
+margin_bottom = 35.0
+
+[node name="Label" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer3"]
+margin_right = 58.0
+margin_bottom = 9.0
+rect_min_size = Vector2( 58, 0 )
+text = "Last Saved:"
+align = 2
+
+[node name="LastSaved" type="Label" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer3"]
+margin_left = 62.0
+margin_right = 180.0
+margin_bottom = 9.0
+size_flags_horizontal = 3
+custom_colors/font_color = Color( 0.6, 0.6, 0.6, 1 )
+text = "0000-00-00 00:00"
+align = 1
+
+[node name="HSeparator" type="HSeparator" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer"]
+margin_top = 39.0
+margin_right = 180.0
+margin_bottom = 43.0
+
+[node name="HBoxContainer4" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer"]
+margin_top = 47.0
+margin_right = 180.0
+margin_bottom = 64.0
+
+[node name="QuickSave" type="Button" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer4"]
+margin_right = 112.0
+margin_bottom = 17.0
+rect_min_size = Vector2( 112, 17 )
+size_flags_horizontal = 3
+text = "Quick Save"
+
+[node name="SaveAs" type="Button" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer4"]
+margin_left = 116.0
+margin_right = 180.0
+margin_bottom = 17.0
+rect_min_size = Vector2( 0, 17 )
+size_flags_horizontal = 3
+text = "Save As..."
+
+[node name="HBoxContainer5" type="HBoxContainer" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer"]
+margin_top = 68.0
+margin_right = 180.0
+margin_bottom = 85.0
+
+[node name="LoadFrom" type="Button" parent="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer5"]
+margin_right = 180.0
+margin_bottom = 17.0
+rect_min_size = Vector2( 80, 17 )
+size_flags_horizontal = 3
+text = "Load World From..."
+
 [node name="HSeparator2" type="HSeparator" parent="CenterContainer/PanelContainer/VBoxContainer"]
 margin_top = 143.0
 margin_right = 229.0
@@ -333,12 +501,17 @@ __meta__ = {
 "_edit_use_anchors_": false
 }
 
+[connection signal="file_selected" from="SaveFileDialog" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World" method="_on_SaveFileDialog_file_selected"]
+[connection signal="file_selected" from="LoadFileDialog" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World" method="_on_LoadFileDialog_file_selected"]
 [connection signal="visibility_changed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Appearance" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Appearance" method="_on_Appearance_visibility_changed"]
 [connection signal="text_changed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Appearance/VBoxContainer/ContainerName/DisplayName" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Appearance" method="_on_DisplayName_text_changed"]
 [connection signal="value_changed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Appearance/VBoxContainer/ContainerColor/Hue" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Appearance" method="_on_Hue_value_changed"]
-[connection signal="text_changed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerServer/ServerPort" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer" method="_on_ServerPort_text_changed"]
-[connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerServer/ServerOpenClose" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer" method="_on_ServerOpenClose_pressed"]
-[connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerClient/ClientDisConnect" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer" method="_on_ClientDisConnect_pressed"]
-[connection signal="toggled" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/ContainerHideAddress/HideAddress" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer" method="_on_HideAddress_toggled"]
+[connection signal="text_changed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerServer/ServerPort" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer" method="_on_ServerPort_text_changed"]
+[connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerServer/ServerOpenClose" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer" method="_on_ServerOpenClose_pressed"]
+[connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerClient/ClientDisConnect" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer" method="_on_ClientDisConnect_pressed"]
+[connection signal="toggled" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer/VBoxContainer/ContainerHideAddress/HideAddress" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/Multiplayer" method="_on_HideAddress_toggled"]
+[connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer4/QuickSave" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World" method="_on_QuickSave_pressed"]
+[connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer4/SaveAs" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World" method="_on_SaveAs_pressed"]
+[connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World/VBoxContainer/HBoxContainer5/LoadFrom" to="CenterContainer/PanelContainer/VBoxContainer/TabContainer/World" method="_on_LoadFrom_pressed"]
 [connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/Quit" to="." method="_on_Quit_pressed"]
 [connection signal="pressed" from="CenterContainer/PanelContainer/VBoxContainer/Return" to="." method="_on_Return_pressed"]
diff --git a/src/CreativeBuilding.cs b/src/CreativeBuilding.cs
index 2cd2d78..517cfd7 100644
--- a/src/CreativeBuilding.cs
+++ b/src/CreativeBuilding.cs
@@ -108,7 +108,7 @@ public class CreativeBuilding : Node2D
             .ToArray();
 
         foreach (var pos in validLocations) {
-            var block = server.Sync.Spawn<Block>();
+            var block = server.Spawn<Block>();
             block.Position = pos;
             block.Color    = player.Color.Blend(Color.FromHsv(0.0F, 0.0F, GD.Randf(), 0.2F));
         }
@@ -122,7 +122,7 @@ public class CreativeBuilding : Node2D
         foreach (var pos in GetBlockPositions(start, direction, length)) {
             var block = server.GetBlockAt(pos);
             if (block?.Unbreakable != false) continue;
-            server.Sync.Destroy(block);
+            block.RemoveFromParent();
         }
     }
 }
diff --git a/src/EscapeMenu.cs b/src/EscapeMenu.cs
index e0470b2..c9416ce 100644
--- a/src/EscapeMenu.cs
+++ b/src/EscapeMenu.cs
@@ -14,7 +14,7 @@ public class EscapeMenu : Control
         Return = GetNode<Button>(ReturnPath);
     }
 
-    public override void _Input(InputEvent @event)
+    public override void _UnhandledInput(InputEvent @event)
     {
         if (@event.IsActionPressed("ui_menu")) Toggle();
     }
diff --git a/src/EscapeMenuMultiplayer.cs b/src/EscapeMenuMultiplayer.cs
index b7c6990..6f8635d 100644
--- a/src/EscapeMenuMultiplayer.cs
+++ b/src/EscapeMenuMultiplayer.cs
@@ -38,7 +38,7 @@ public class EscapeMenuMultiplayer : Container
     private void SetupIntegratedServer()
     {
         IntegratedServer = new IntegratedServer();
-        this.GetClient().AddChild(IntegratedServer);
+        this.GetClient().AddChild(IntegratedServer, true);
         CallDeferred(nameof(StartIntegratedServerAndConnect));
     }
     private void StartIntegratedServerAndConnect()
@@ -137,14 +137,11 @@ public class EscapeMenuMultiplayer : Container
             IntegratedServer.Server.Stop();
             // TODO: Have a single method to "reset" the state?
             IntegratedServer.Server.Objects.Clear();
-            IntegratedServer.Server.Sync.Clear();
-            IntegratedServer.GetParent().RemoveChild(IntegratedServer);
-            IntegratedServer.QueueFree();
+            IntegratedServer.RemoveFromParent();
             IntegratedServer = null;
 
             client.Disconnect();
             client.Objects.Clear();
-            client.Sync.Clear();
         }
 
         if (client.Status == ConnectionStatus.Disconnected) {
@@ -160,7 +157,6 @@ public class EscapeMenuMultiplayer : Container
         } else {
             client.Disconnect();
             client.Objects.Clear();
-            client.Sync.Clear();
         }
     }
 }
diff --git a/src/EscapeMenuWorld.cs b/src/EscapeMenuWorld.cs
new file mode 100644
index 0000000..79228a6
--- /dev/null
+++ b/src/EscapeMenuWorld.cs
@@ -0,0 +1,133 @@
+using System;
+using System.Text;
+using Godot;
+using Path = System.IO.Path;
+using File = System.IO.File;
+using Directory = System.IO.Directory;
+using System.Linq;
+using static Godot.NetworkedMultiplayerPeer;
+
+public class EscapeMenuWorld : CenterContainer
+{
+    [Export] public NodePath FilenamePath { get; set; }
+    [Export] public NodePath LastSavedPath { get; set; }
+    [Export] public NodePath PlaytimePath { get; set; }
+    [Export] public NodePath QuickSavePath { get; set; }
+    [Export] public NodePath SaveAsPath { get; set; }
+    [Export] public NodePath SaveFileDialogPath { get; set; }
+    [Export] public NodePath LoadFileDialogPath { get; set; }
+
+    public Label FilenameLabel { get; private set; }
+    public Label LastSavedLabel { get; private set; }
+    public Label PlaytimeLabel { get; private set; }
+    public Button QuickSaveButton { get; private set; }
+    public Button SaveAsButton { get; private set; }
+    public FileDialog SaveFileDialog { get; private set; }
+    public FileDialog LoadFileDialog { get; private set; }
+
+    private Node _world;
+    private TimeSpan _playtime;
+    private string _currentWorld;
+
+    public override void _Ready()
+    {
+        _world = this.GetClient().GetNode("World");
+
+        FilenameLabel  = GetNode<Label>(FilenamePath);
+        LastSavedLabel = GetNode<Label>(LastSavedPath);
+        PlaytimeLabel  = GetNode<Label>(PlaytimePath);
+        QuickSaveButton = GetNode<Button>(QuickSavePath);
+        SaveAsButton    = GetNode<Button>(SaveAsPath);
+        SaveFileDialog = GetNode<FileDialog>(SaveFileDialogPath);
+        LoadFileDialog = GetNode<FileDialog>(LoadFileDialogPath);
+
+        // TODO: Reset this when going back to singleplayer after having connected to a multiplayer server.
+        QuickSaveButton.Visible = false;
+        SaveAsButton.Text = "Save World As...";
+        SaveFileDialog.GetOk().Text = "Save";
+
+        var worldsFolder = OS.GetUserDataDir() + "/worlds/";
+        Directory.CreateDirectory(worldsFolder);
+        SaveFileDialog.CurrentPath = worldsFolder;
+        LoadFileDialog.CurrentPath = worldsFolder;
+
+        this.GetClient().StatusChanged += OnStatusChanged;
+    }
+
+    public override void _Process(float delta)
+    {
+        if (!GetTree().Paused || (_world.PauseMode != PauseModeEnum.Stop))
+            _playtime += TimeSpan.FromSeconds(delta);
+
+        var b = new StringBuilder();
+        if (_playtime.Days > 0) b.Append(_playtime.Days).Append("d ");
+        if (_playtime.Hours > 0) b.Append(_playtime.Hours).Append("h ");
+        if (_playtime.Minutes < 10) b.Append('0'); b.Append(_playtime.Minutes).Append("m ");
+        if (_playtime.Seconds < 10) b.Append('0'); b.Append(_playtime.Seconds).Append("s");
+        PlaytimeLabel.Text = b.ToString();
+    }
+
+    private void OnStatusChanged(ConnectionStatus status)
+    {
+        var server = this.GetClient().GetNode<IntegratedServer>(nameof(IntegratedServer));
+        GetParent<TabContainer>().SetTabDisabled(GetIndex(), server == null);
+    }
+
+
+    #pragma warning disable IDE0051
+    #pragma warning disable IDE1006
+
+    private void _on_QuickSave_pressed()
+        => _on_SaveFileDialog_file_selected(_currentWorld);
+
+    private void _on_SaveAs_pressed()
+    {
+        SaveFileDialog.Invalidate();
+        SaveFileDialog.PopupCenteredClamped(new Vector2(480, 320), 0.85F);
+    }
+
+    private void _on_SaveFileDialog_file_selected(string path)
+    {
+        var server = this.GetClient().GetNode<IntegratedServer>(nameof(IntegratedServer)).Server;
+        var save   = Save.CreateFromWorld(server, _playtime);
+        save.WriteToFile(path + ".tmp");
+        File.Delete(path); // TODO: In later .NET, there is a File.Move(source, dest, overwrite).
+        File.Move(path + ".tmp", path);
+
+        _currentWorld = path;
+        FilenameLabel.Text = Path.GetFileName(path);
+        LastSavedLabel.Text = save.LastSaved.ToString("yyyy-MM-dd HH:mm");
+        QuickSaveButton.Visible = true;
+        SaveAsButton.Text = "Save As...";
+    }
+
+    private void _on_LoadFrom_pressed()
+    {
+        LoadFileDialog.Invalidate();
+        LoadFileDialog.PopupCenteredClamped(new Vector2(480, 320), 0.85F);
+    }
+
+    private void _on_LoadFileDialog_file_selected(string path)
+    {
+        var server = this.GetClient().GetNode<IntegratedServer>(nameof(IntegratedServer)).Server;
+        var save   = Save.ReadFromFile(path);
+
+        // Clear out all objects that have a SaveAttribute.
+        var objectsToRemove = server.Objects.Select(x => x.Item2)
+            .Where(x => SaveRegistry.GetOrNull(x.GetType()) != null).ToArray();
+        foreach (var obj in objectsToRemove) obj.RemoveFromParent();
+
+        // Reset players' positions.
+        foreach (var (id, player) in server.Players)
+            player.RPC(new []{ id }, player.ResetPosition, Vector2.Zero);
+
+        save.AddToWorld(server);
+        _playtime = save.Playtime;
+
+        _currentWorld = path;
+        FilenameLabel.Text = Path.GetFileName(path);
+        LastSavedLabel.Text = save.LastSaved.ToString("yyyy-MM-dd HH:mm");
+        QuickSaveButton.Visible = true;
+        SaveAsButton.Text = "Save As...";
+    }
+}
diff --git a/src/IO/DeSerializer.Impl.cs b/src/IO/DeSerializer.Impl.cs
index ddafc51..1c2061f 100644
--- a/src/IO/DeSerializer.Impl.cs
+++ b/src/IO/DeSerializer.Impl.cs
@@ -199,7 +199,7 @@ public class DictionaryDeSerializerGenerator
             var dictionary = new TDictionary();
             for (var i = 0; i < count; i++)
                 dictionary.Add((TKey)_keyDeSerializer.Deserialize(game, reader),
-                                (TValue)_valueDeSerializer.Deserialize(game, reader));
+                               (TValue)_valueDeSerializer.Deserialize(game, reader));
             return dictionary;
         }
     }
@@ -224,7 +224,7 @@ public class NodeDeSerializerGenerator
         public override TObj Deserialize(Game game, BinaryReader reader)
         {
             var id    = new UniqueID(reader.ReadUInt32());
-            var value = (TObj)game.Objects.GetNodeByID(id);
+            var value = (TObj)game.Objects.GetObjectByID(id);
             if (value == null) throw new Exception($"Could not find synced object of type {typeof(TObj)} with ID {id}");
             return value;
         }
@@ -232,31 +232,30 @@ public class NodeDeSerializerGenerator
 }
 
 // TODO: Replace this with something that will generate code at runtime for improved performance.
-public class ComplexDeSerializer
-    : IDeSerializer
+public class ComplexDeSerializer<T>
+    : DeSerializer<T>
 {
-    private readonly Type _type;
     private event Action<Game, BinaryWriter, object> OnSerialize;
     private event Action<Game, BinaryReader, object> OnDeserialize;
 
-    public ComplexDeSerializer(Type type)
+    public ComplexDeSerializer()
     {
-        _type = type;
-        foreach (var field in type.GetFields(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic)) {
+        foreach (var field in typeof(T).GetFields(BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic)) {
             var deSerializer = DeSerializerRegistry.Get(field.FieldType, true);
-            OnSerialize += (game, writer, value) => deSerializer.Serialize(game, writer, field.GetValue(value));
-            OnDeserialize += (game, reader, instance) => field.SetValue(instance, deSerializer.Deserialize(game, reader));
+            OnSerialize   += (game, writer, obj) => deSerializer.Serialize(game, writer, field.GetValue(obj));
+            OnDeserialize += (game, reader, obj) => field.SetValue(obj, deSerializer.Deserialize(game, reader));
         }
         if (OnSerialize == null) throw new InvalidOperationException(
-            $"Unable to create serializer for type {type}");
+            $"Unable to create {nameof(ComplexDeSerializer<T>)} for type {typeof(T)}");
     }
 
-    public void Serialize(Game game, BinaryWriter writer, object value)
+    public override void Serialize(Game game, BinaryWriter writer, T value)
         => OnSerialize(game, writer, value);
-    public object Deserialize(Game game, BinaryReader reader)
+
+    public override T Deserialize(Game game, BinaryReader reader)
     {
-        var instance = FormatterServices.GetUninitializedObject(_type);
-        OnDeserialize(game, reader, instance);
-        return instance;
+        var value = FormatterServices.GetUninitializedObject(typeof(T));
+        OnDeserialize(game, reader, value);
+        return (T)value;
     }
 }
diff --git a/src/IO/DeSerializerRegistry.cs b/src/IO/DeSerializerRegistry.cs
index eaa344c..8748917 100644
--- a/src/IO/DeSerializerRegistry.cs
+++ b/src/IO/DeSerializerRegistry.cs
@@ -56,8 +56,12 @@ public static class DeSerializerRegistry
             if (!createIfMissing) throw new InvalidOperationException(
                 $"No DeSerializer for type {type} found");
 
-            value = _generators.Select(g => g.GenerateFor(type)).FirstOrDefault(x => x != null);
-            if (value == null) value = new ComplexDeSerializer(type);
+            value = _generators.Select(g => g.GenerateFor(type))
+                               .FirstOrDefault(x => x != null);
+            if (value == null) {
+                var deSerializerType = typeof(ComplexDeSerializer<>).MakeGenericType(type);
+                value = (IDeSerializer)Activator.CreateInstance(deSerializerType);
+            }
             _byType.Add(type, value);
         }
         return value;
diff --git a/src/IO/PropertyDeSerializer.cs b/src/IO/PropertyDeSerializer.cs
new file mode 100644
index 0000000..ed02a30
--- /dev/null
+++ b/src/IO/PropertyDeSerializer.cs
@@ -0,0 +1,48 @@
+using System;
+using System.Reflection;
+
+public interface IPropertyDeSerializer
+{
+    PropertyInfo Property { get; }
+    Type Type { get; }
+    string Name { get; }
+    string FullName { get; }
+    int HashID { get; }
+
+    IDeSerializer DeSerializer { get; }
+    object Get(object obj);
+    void Set(object obj, object value);
+}
+
+public class PropertyDeSerializer<TObj, TProp>
+    : IPropertyDeSerializer
+{
+    public PropertyInfo Property { get; }
+    public Type Type => Property.PropertyType;
+    public string Name => Property.Name;
+    public string FullName { get; }
+    public int HashID { get; }
+
+    public IDeSerializer<TProp> DeSerializer { get; }
+    public Func<TObj, TProp> Getter { get; }
+    public Action<TObj, TProp> Setter { get; }
+
+    public PropertyDeSerializer(PropertyInfo property)
+    {
+        if ((property.GetMethod == null) || (property.SetMethod == null)) throw new Exception(
+            $"Property {property.DeclaringType}.{property.Name} must have a getter and setter defined");
+
+        Property = property;
+        FullName = $"{Property.DeclaringType.FullName}.{Property.Name}";
+        HashID   = FullName.GetDeterministicHashCode();
+
+        DeSerializer = DeSerializerRegistry.Get<TProp>(true);
+        Getter = (Func<TObj, TProp>)Property.GetMethod.CreateDelegate(typeof(Func<TObj, TProp>));
+        Setter = (Action<TObj, TProp>)Property.SetMethod.CreateDelegate(typeof(Action<TObj, TProp>));
+    }
+
+    // IPropertyDeSerializer implementation
+    IDeSerializer IPropertyDeSerializer.DeSerializer => DeSerializer;
+    object IPropertyDeSerializer.Get(object obj) => Getter((TObj)obj);
+    void IPropertyDeSerializer.Set(object obj, object value) => Setter((TObj)obj, (TProp)value);
+}
diff --git a/src/IO/Save.cs b/src/IO/Save.cs
index 6eef1dd..740b94a 100644
--- a/src/IO/Save.cs
+++ b/src/IO/Save.cs
@@ -1,7 +1,103 @@
 using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using Godot;
+using File = System.IO.File;
 
-[AttributeUsage(AttributeTargets.Property)]
-public class SaveAttribute : Attribute
+public class Save
 {
+    public const string FILE_EXT     = ".yf5";
+    public const int MAGIC_NUMBER    = 0x59463573; // "YF5s"
+    public const int CURRENT_VERSION = 0;
 
+    public int Version { get; private set; }
+    public DateTime LastSaved { get; private set; }
+    public TimeSpan Playtime { get; set; }
+
+    public List<(SaveObjectInfo, List<object>)> Objects { get; private set; }
+
+
+    public static Save ReadFromFile(string path)
+    {
+        var save = new Save { LastSaved = File.GetLastAccessTime(path) };
+        using (var stream = File.OpenRead(path)) {
+            using (var reader = new BinaryReader(stream)) {
+                var magic = reader.ReadInt32();
+                if (magic != MAGIC_NUMBER) throw new IOException(
+                    $"Magic number does not match ({magic:X8} != {MAGIC_NUMBER:X8})");
+
+                // TODO: See how to support multiple versions.
+                save.Version = reader.ReadUInt16();
+                if (save.Version != CURRENT_VERSION) throw new IOException(
+                    $"Version does not match ({save.Version} != {CURRENT_VERSION})");
+
+                save.Playtime = TimeSpan.FromSeconds(reader.ReadUInt32());
+
+                var numObjects = reader.ReadInt32();
+                save.Objects = new List<(SaveObjectInfo, List<object>)>(numObjects);
+                for (var i = 0; i < numObjects; i++) {
+                    var hashID  = reader.ReadInt32();
+                    var objInfo = SaveRegistry.GetOrThrow(hashID);
+                    var props = objInfo.PropertiesByID.Select(x => x.DeSerializer.Deserialize(null, reader)).ToList();
+                    save.Objects.Add((objInfo, props));
+                }
+            }
+        }
+        return save;
+    }
+
+    public void WriteToFile(string path)
+    {
+        using (var stream = File.OpenWrite(path)) {
+            using (var writer = new BinaryWriter(stream)) {
+                writer.Write(MAGIC_NUMBER);
+                writer.Write((ushort)CURRENT_VERSION);
+                writer.Write((uint)Playtime.TotalSeconds);
+
+                writer.Write(Objects.Count);
+                foreach (var (objInfo, props) in Objects) {
+                    writer.Write(objInfo.HashID);
+                    for (var i = 0; i < objInfo.PropertiesByID.Count; i++) {
+                        var propInfo  = objInfo.PropertiesByID[i];
+                        var propValue = props[i];
+                        propInfo.DeSerializer.Serialize(null, writer, propValue);
+                    }
+                }
+            }
+        }
+        LastSaved = File.GetLastAccessTime(path);
+    }
+
+
+    public static Save CreateFromWorld(Game game, TimeSpan playtime)
+    {
+        var save = new Save {
+            Playtime = playtime,
+            Objects  = new List<(SaveObjectInfo, List<object>)>(),
+        };
+        foreach (var (id, obj) in game.Objects) {
+            var objInfo = SaveRegistry.GetOrNull(obj.GetType());
+            if (objInfo == null) continue;
+
+            var props = objInfo.PropertiesByID.Select(x => x.Get(obj)).ToList();
+            save.Objects.Add((objInfo, props));
+        }
+        return save;
+    }
+
+    public void AddToWorld(Server server)
+    {
+        foreach (var (objInfo, props) in Objects) {
+            var obj = objInfo.SpawnInfo.Scene.Init<Node>();
+            server.GetNode("World").AddChild(obj, true);
+            server.Objects.Add(null, obj);
+
+            for (var i = 0; i < objInfo.PropertiesByID.Count; i++) {
+                var propInfo  = objInfo.PropertiesByID[i];
+                var propValue = props[i];
+                propInfo.Set(obj, propValue);
+            }
+        }
+    }
 }
diff --git a/src/IO/SaveRegistry.cs b/src/IO/SaveRegistry.cs
new file mode 100644
index 0000000..6d4bde6
--- /dev/null
+++ b/src/IO/SaveRegistry.cs
@@ -0,0 +1,69 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using Godot;
+
+public static class SaveRegistry
+{
+    private static readonly Dictionary<int, SaveObjectInfo> _byID = new Dictionary<int, SaveObjectInfo>();
+    private static readonly Dictionary<Type, SaveObjectInfo> _byType = new Dictionary<Type, SaveObjectInfo>();
+
+    static SaveRegistry()
+    {
+        foreach (var type in typeof(SyncRegistry).Assembly.GetTypes()) {
+            var syncAttr = type.GetCustomAttribute<SaveAttribute>();
+            if (syncAttr == null) continue;
+
+            if (!typeof(Node).IsAssignableFrom(type)) throw new Exception(
+                $"Type {type} with {nameof(SyncAttribute)} must be a subclass of {nameof(Node)}");
+
+            var spawnInfo = SpawnRegistry.Get(type);
+            var objInfo   = new SaveObjectInfo(type, spawnInfo);
+
+            foreach (var property in type.GetProperties()) {
+                if (property.GetCustomAttribute<SaveAttribute>() == null) continue;
+                var propType = typeof(PropertyDeSerializer<,>).MakeGenericType(type, property.PropertyType);
+                var propDeSerializer = (IPropertyDeSerializer)Activator.CreateInstance(propType, property);
+                objInfo.PropertiesByName.Add(propDeSerializer.Name, propDeSerializer);
+            }
+            objInfo.PropertiesByID.AddRange(objInfo.PropertiesByName.Values.OrderBy(x => x.HashID));
+
+            _byID.Add(objInfo.HashID, objInfo);
+            _byType.Add(objInfo.Type, objInfo);
+        }
+    }
+
+    public static SaveObjectInfo GetOrNull(int hashID)
+        => _byID.TryGetValue(hashID, out var value) ? value : null;
+    public static SaveObjectInfo GetOrThrow(int hashID) => GetOrNull(hashID)
+        ?? throw new Exception($"Unknown {nameof(SaveObjectInfo)} with HashID {hashID}");
+
+    public static SaveObjectInfo GetOrNull<T>() => GetOrNull(typeof(T));
+    public static SaveObjectInfo GetOrNull(Type type) => _byType.TryGetValue(type, out var value) ? value : null;
+
+    public static SaveObjectInfo GetOrThrow<T>() => GetOrThrow(typeof(T));
+    public static SaveObjectInfo GetOrThrow(Type type) => GetOrNull(type) ?? throw new Exception(
+        $"No {nameof(SaveObjectInfo)} found for type {type} (missing {nameof(SyncAttribute)}?)");
+}
+
+public class SaveObjectInfo
+{
+    public Type Type { get; }
+    public int HashID { get; }
+    public SpawnInfo SpawnInfo { get; }
+    public string Name => Type.Name;
+
+    public List<IPropertyDeSerializer> PropertiesByID { get; } = new List<IPropertyDeSerializer>();
+    public Dictionary<string, IPropertyDeSerializer> PropertiesByName { get; } = new Dictionary<string, IPropertyDeSerializer>();
+
+    public SaveObjectInfo(Type type, SpawnInfo spawnInfo)
+    {
+        Type   = type;
+        HashID = type.FullName.GetDeterministicHashCode();
+        SpawnInfo = spawnInfo;
+    }
+}
+
+[AttributeUsage(AttributeTargets.Class | AttributeTargets.Property)]
+public class SaveAttribute : Attribute {  }
diff --git a/src/Network/IntegratedServer.cs b/src/Network/IntegratedServer.cs
index 02e5593..2e337a9 100644
--- a/src/Network/IntegratedServer.cs
+++ b/src/Network/IntegratedServer.cs
@@ -5,6 +5,8 @@ public class IntegratedServer : Node
     private SceneTree _sceneTree;
     public Server Server { get; private set; }
 
+    public IntegratedServer() => Name = "IntegratedServer";
+
     public override void _Ready()
     {
         _sceneTree = new SceneTree();
@@ -12,13 +14,13 @@ public class IntegratedServer : Node
         _sceneTree.Root.RenderTargetUpdateMode = Godot.Viewport.UpdateMode.Disabled;
 
         var scene = GD.Load<PackedScene>("res://scene/ServerScene.tscn").Init<Server>();
-        _sceneTree.Root.AddChild(scene);
+        _sceneTree.Root.AddChild(scene, true);
         _sceneTree.CurrentScene = scene;
 
         Server = _sceneTree.Root.GetChild<Server>(0);
         // Spawn default blocks.
         for (var x = -6; x <= 6; x++) {
-            var block = Server.Sync.Spawn<Block>();
+            var block = Server.Spawn<Block>();
             block.Position    = new BlockPos(x, 3);
             block.Color       = Color.FromHsv(GD.Randf(), 0.1F, 1.0F);
             block.Unbreakable = true;
diff --git a/src/Network/Sync.cs b/src/Network/Sync.cs
index 9b89cad..5febc60 100644
--- a/src/Network/Sync.cs
+++ b/src/Network/Sync.cs
@@ -6,14 +6,52 @@ using Godot;
 
 // TODO: Allow syncronization of child objects spawned with their parent objects.
 // TODO: Specify who properties are syncronized with. (Owner, Friends, Team, Everyone)
-public class Sync
+public abstract class Sync
 {
     protected Game Game { get; }
     protected Dictionary<UniqueID, SyncStatus> StatusByID { get; } = new Dictionary<UniqueID, SyncStatus>();
     protected Dictionary<Node, SyncStatus> StatusByObject { get; } = new Dictionary<Node, SyncStatus>();
 
-    static Sync() => DeSerializerRegistry.Register(new SyncPacketObjectDeSerializer());
-    public Sync(Game game) => Game = game;
+    static Sync()
+        => DeSerializerRegistry.Register(new SyncPacketObjectDeSerializer());
+
+    public Sync(Game game)
+    {
+        Game = game;
+        Game.Objects.Added   += OnObjectAdded;
+        Game.Objects.Removed += OnObjectRemoved;
+        Game.Objects.Cleared += OnObjectsCleared;
+    }
+
+    private void OnObjectAdded(UniqueID id, Node obj)
+    {
+        var info = SyncRegistry.GetOrNull(obj.GetType());
+        if (info == null) return;
+
+        var status = new SyncStatus(id, obj, info);
+        StatusByID.Add(id, status);
+        StatusByObject.Add(obj, status);
+        OnSyncedAdded(status);
+    }
+
+    private void OnObjectRemoved(UniqueID id, Node obj)
+    {
+        if (!StatusByObject.TryGetValue(obj, out var status)) return;
+
+        StatusByID.Remove(status.ID);
+        StatusByObject.Remove(status.Object);
+        OnSyncedRemoved(status);
+    }
+
+    protected virtual void OnSyncedAdded(SyncStatus status) {  }
+    protected virtual void OnSyncedRemoved(SyncStatus status) {  }
+
+    private void OnObjectsCleared()
+    {
+        StatusByID.Clear();
+        StatusByObject.Clear();
+    }
+
 
     public SyncStatus GetStatusOrNull(UniqueID id)
         => StatusByID.TryGetValue(id, out var value) ? value : null;
@@ -30,18 +68,6 @@ public class Sync
     public SyncStatus GetStatusOrThrow(Node obj)
         => GetStatusOrNull(obj) ?? throw new Exception(
             $"No {nameof(SyncStatus)} found for '{obj.Name}' ({obj.GetType()})");
-
-    public virtual void Clear()
-    {
-        foreach (var (node, _) in StatusByObject) {
-            if (!Godot.Object.IsInstanceValid(node)) continue;
-            node.GetParent().RemoveChild(node);
-            node.QueueFree();
-        }
-
-        StatusByID.Clear();
-        StatusByObject.Clear();
-    }
 }
 
 
@@ -91,12 +117,11 @@ internal class SyncPacketObjectDeSerializer
         writer.Write((byte)value.Mode);
         writer.Write((byte)value.Values.Count);
 
-        var objInfo = SyncRegistry.Get(value.InfoID);
+        var objInfo = SyncRegistry.GetOrThrow(value.InfoID);
         foreach (var (propID, val) in value.Values) {
             writer.Write(propID);
             var propInfo = objInfo.PropertiesByID[propID];
-            var deSerializer = DeSerializerRegistry.Get(propInfo.Type, false);
-            deSerializer.Serialize(game, writer, val);
+            propInfo.DeSerializer.Serialize(game, writer, val);
         }
     }
 
@@ -107,7 +132,7 @@ internal class SyncPacketObjectDeSerializer
         var mode   = (SyncMode)reader.ReadByte();
         var count  = reader.ReadByte();
 
-        var objInfo = SyncRegistry.Get(infoID);
+        var objInfo = SyncRegistry.GetOrThrow(infoID);
         if (count > objInfo.PropertiesByID.Count) throw new Exception(
             $"Count is higher than possible number of changes");
 
@@ -120,8 +145,7 @@ internal class SyncPacketObjectDeSerializer
             var propInfo = objInfo.PropertiesByID[propID];
             if (!duplicateCheck.Add(propID)) throw new Exception(
                 $"Duplicate entry for property {propInfo.Name}");
-            var deSerializer = DeSerializerRegistry.Get(propInfo.Type, false);
-            values.Add((propID, deSerializer.Deserialize(game, reader)));
+            values.Add((propID, propInfo.DeSerializer.Deserialize(game, reader)));
         }
 
         return new SyncPacket.Object(infoID, id, mode, values);
diff --git a/src/Network/SyncClient.cs b/src/Network/SyncClient.cs
index ecce7cf..df2b315 100644
--- a/src/Network/SyncClient.cs
+++ b/src/Network/SyncClient.cs
@@ -13,21 +13,17 @@ public class SyncClient : Sync
     private void OnSyncPacket(Game _, NetworkID networkID, SyncPacket packet)
     {
         foreach (var packetObj in packet.Changes) {
-            var info   = SyncRegistry.Get(packetObj.InfoID);
+            var info   = SyncRegistry.GetOrThrow(packetObj.InfoID);
             var status = GetStatusOrNull(packetObj.ID);
 
             if (status == null) {
                 if (packetObj.Mode != SyncMode.Spawn) throw new Exception(
                     $"Unknown synced object {info.Name} (ID {packetObj.ID})");
 
-                var obj = info.Scene.Init<Node>();
+                var obj = info.SpawnInfo.Scene.Init<Node>();
+                Client.GetNode("World").AddChild(obj, true);
                 Client.Objects.Add(packetObj.ID, obj);
-
-                status = new SyncStatus(packetObj.ID, obj, info);
-                StatusByID.Add(status.ID, status);
-                StatusByObject.Add(status.Object, status);
-
-                Client.GetNode("World").AddChild(obj);
+                status = GetStatusOrThrow(packetObj.ID);
             } else {
                 if (packetObj.Mode == SyncMode.Spawn) throw new Exception(
                     $"Spawning object {info.Name} with ID {packetObj.ID}, but it already exists");
@@ -35,18 +31,14 @@ public class SyncClient : Sync
                     $"Info of synced object being modified doesn't match ({info.Name} != {status.Info.Name})");
 
                 if (packetObj.Mode == SyncMode.Destroy) {
-                    StatusByID.Remove(status.ID);
-                    StatusByObject.Remove(status.Object);
-
-                    status.Object.GetParent().RemoveChild(status.Object);
-                    status.Object.QueueFree();
+                    status.Object.RemoveFromParent();
                     continue;
                 }
             }
 
             foreach (var (propID, value) in packetObj.Values) {
-                var propInfo = info.PropertiesByID[propID];
-                propInfo.Setter(status.Object, value);
+                var propDeSerializer = info.PropertiesByID[propID];
+                propDeSerializer.Set(status.Object, value);
             }
         }
     }
diff --git a/src/Network/SyncRegistry.cs b/src/Network/SyncRegistry.cs
index 197575d..2fad1f1 100644
--- a/src/Network/SyncRegistry.cs
+++ b/src/Network/SyncRegistry.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Reflection;
 using Godot;
 
@@ -11,86 +12,54 @@ public static class SyncRegistry
     static SyncRegistry()
     {
         foreach (var type in typeof(SyncRegistry).Assembly.GetTypes()) {
-            var objAttr = type.GetCustomAttribute<SyncAttribute>();
-            if (objAttr == null) continue;
+            var syncAttr = type.GetCustomAttribute<SyncAttribute>();
+            if (syncAttr == null) continue;
 
             if (!typeof(Node).IsAssignableFrom(type)) throw new Exception(
                 $"Type {type} with {nameof(SyncAttribute)} must be a subclass of {nameof(Node)}");
 
-            var objInfo = new SyncObjectInfo((ushort)_byID.Count, type);
+            var spawnInfo = SpawnRegistry.Get(type);
+            var objInfo   = new SyncObjectInfo(type, spawnInfo);
+
             foreach (var property in type.GetProperties()) {
                 if (property.GetCustomAttribute<SyncAttribute>() == null) continue;
-                var propType = typeof(SyncPropertyInfo<,>).MakeGenericType(type, property.PropertyType);
-                var propInfo = (SyncPropertyInfo)Activator.CreateInstance(propType, (byte)objInfo.PropertiesByID.Count, property);
-                objInfo.PropertiesByID.Add(propInfo);
-                objInfo.PropertiesByName.Add(propInfo.Name, propInfo);
-
-                // Ensure that the de/serializer for this type has been generated.
-                DeSerializerRegistry.Get(propInfo.Type, true);
+                var propType = typeof(PropertyDeSerializer<,>).MakeGenericType(type, property.PropertyType);
+                var propDeSerializer = (IPropertyDeSerializer)Activator.CreateInstance(propType, property);
+                objInfo.PropertiesByName.Add(propDeSerializer.Name, propDeSerializer);
             }
-            _byID.Add(objInfo);
+            objInfo.PropertiesByID.AddRange(objInfo.PropertiesByName.Values.OrderBy(x => x.HashID));
+
             _byType.Add(objInfo.Type, objInfo);
         }
+        _byID.AddRange(_byType.Values.OrderBy(x => x.Name.GetDeterministicHashCode()));
+        for (ushort i = 0; i < _byID.Count; i++) _byID[i].ID = i;
     }
 
-    public static SyncObjectInfo Get(ushort id)
+    public static SyncObjectInfo GetOrThrow(ushort id)
         => (id < _byID.Count) ? _byID[id] : throw new Exception(
             $"Unknown {nameof(SyncObjectInfo)} with ID {id}");
 
-    public static SyncObjectInfo Get<T>()
-        => Get(typeof(T));
-    public static SyncObjectInfo Get(Type type)
-        => _byType.TryGetValue(type, out var value) ? value : throw new Exception(
-            $"No {nameof(SyncObjectInfo)} found for type {type} (missing {nameof(SyncAttribute)}?)");
-}
+    public static SyncObjectInfo GetOrNull<T>() => GetOrNull(typeof(T));
+    public static SyncObjectInfo GetOrNull(Type type) => _byType.TryGetValue(type, out var value) ? value : null;
 
+    public static SyncObjectInfo GetOrThrow<T>() => GetOrThrow(typeof(T));
+    public static SyncObjectInfo GetOrThrow(Type type) => GetOrNull(type) ?? throw new Exception(
+        $"No {nameof(SyncObjectInfo)} found for type {type} (missing {nameof(SyncAttribute)}?)");
+}
 
 public class SyncObjectInfo
 {
-    public ushort ID { get; }
+    public ushort ID { get; internal set; }
     public Type Type { get; }
-    public PackedScene Scene { get; }
+    public SpawnInfo SpawnInfo { get; }
     public string Name => Type.Name;
 
-    public List<SyncPropertyInfo> PropertiesByID { get; } = new List<SyncPropertyInfo>();
-    public Dictionary<string, SyncPropertyInfo> PropertiesByName { get; } = new Dictionary<string, SyncPropertyInfo>();
-
-    public SyncObjectInfo(ushort id, Type type)
-    {
-        ID    = id;
-        Type  = type;
-        Scene = GD.Load<PackedScene>($"res://scene/{type.Name}.tscn");
-    }
-}
-
-public abstract class SyncPropertyInfo
-{
-    public byte ID { get; }
-    public PropertyInfo Property { get; }
-    public string Name => Property.Name;
-    public Type Type => Property.PropertyType;
-
-    public Func<object, object> Getter { get; }
-    public Action<object, object> Setter { get; }
-
-    public SyncPropertyInfo(byte id, PropertyInfo property,
-        Func<object, object> getter, Action<object, object> setter)
-    {
-        ID = id; Property = property;
-        Getter = getter; Setter = setter;
-    }
-}
+    public List<IPropertyDeSerializer> PropertiesByID { get; } = new List<IPropertyDeSerializer>();
+    public Dictionary<string, IPropertyDeSerializer> PropertiesByName { get; } = new Dictionary<string, IPropertyDeSerializer>();
 
-public class SyncPropertyInfo<TObject, TValue> : SyncPropertyInfo
-{
-    public SyncPropertyInfo(byte id, PropertyInfo property) : base(id, property,
-        obj => ((Func<TObject, TValue>)property.GetMethod.CreateDelegate(typeof(Func<TObject, TValue>))).Invoke((TObject)obj),
-        (obj, value) => ((Action<TObject, TValue>)property.SetMethod.CreateDelegate(typeof(Action<TObject, TValue>))).Invoke((TObject)obj, (TValue)value)
-    ) {  }
+    public SyncObjectInfo(Type type, SpawnInfo spawnInfo)
+        { Type = type; SpawnInfo = spawnInfo; }
 }
 
-
 [AttributeUsage(AttributeTargets.Class | AttributeTargets.Property)]
-public class SyncAttribute : Attribute
-{
-}
+public class SyncAttribute : Attribute {  }
diff --git a/src/Network/SyncServer.cs b/src/Network/SyncServer.cs
index c0eae6d..cf581f3 100644
--- a/src/Network/SyncServer.cs
+++ b/src/Network/SyncServer.cs
@@ -9,48 +9,31 @@ public class SyncServer : Sync
 
     protected Server Server => (Server)Game;
 
-    public SyncServer(Server server)
-        : base(server) {  }
+    public SyncServer(Server server) : base(server)
+        => server.Objects.Cleared += _dirtyObjects.Clear;
 
-    public T Spawn<T>()
-        where T : Node
+    protected override void OnSyncedAdded(SyncStatus status)
     {
-        var info = SyncRegistry.Get<T>();
-        var obj  = info.Scene.Init<T>();
-        var id   = Server.Objects.Add(obj);
-
-        var status = new SyncStatus(id, obj, info){ Mode = SyncMode.Spawn };
-        StatusByID.Add(status.ID, status);
-        StatusByObject.Add(status.Object, status);
+        status.Mode = SyncMode.Spawn;
         _dirtyObjects.Add(status);
-
-        Server.GetNode("World").AddChild(obj);
-
-        return obj;
     }
 
-    // TODO: Do this automatically if the node is removed from the tree?
-    public void Destroy(Node obj)
+    protected override void OnSyncedRemoved(SyncStatus status)
     {
-        var status = GetStatusOrThrow(obj);
-
         status.Mode = SyncMode.Destroy;
-        StatusByID.Remove(status.ID);
-        StatusByObject.Remove(status.Object);
         _dirtyObjects.Add(status);
-
-        obj.GetParent().RemoveChild(obj);
-        obj.QueueFree();
     }
 
+
     public void MarkDirty(Node obj, string property)
     {
         var status = GetStatusOrThrow(obj);
-        if (!status.Info.PropertiesByName.TryGetValue(property, out var propInfo)) throw new ArgumentException(
-            $"No {nameof(SyncPropertyInfo)} found for {obj.GetType()}.{property} (missing {nameof(SyncAttribute)}?)", nameof(property));
+        if (!status.Info.PropertiesByName.TryGetValue(property, out var propDeSerializer)) throw new ArgumentException(
+            $"No {nameof(IPropertyDeSerializer)} found for {obj.GetType()}.{property} (missing {nameof(SyncAttribute)}?)", nameof(property));
         if (!(obj.GetGame() is Server)) return;
 
-        status.DirtyProperties |= 1 << propInfo.ID;
+        var index = status.Info.PropertiesByID.IndexOf(propDeSerializer);
+        status.DirtyProperties |= 1 << index;
         _dirtyObjects.Add(status);
     }
 
@@ -62,9 +45,10 @@ public class SyncServer : Sync
         var packet = new SyncPacket();
         foreach (var status in _dirtyObjects) {
             var values = new List<(byte, object)>();
-            foreach (var prop in status.Info.PropertiesByID)
-                if ((status.DirtyProperties & (1 << prop.ID)) != 0)
-                    values.Add((prop.ID, prop.Getter(status.Object)));
+            if (status.Mode != SyncMode.Destroy)
+                for (byte i = 0; i < status.Info.PropertiesByID.Count; i++)
+                    if ((status.DirtyProperties & (1 << i)) != 0)
+                        values.Add((i, status.Info.PropertiesByID[i].Get(status.Object)));
             packet.Changes.Add(new SyncPacket.Object(status.Info.ID, status.ID, status.Mode, values));
             // If the object has been newly spawned, now is the time to remove the "Spawn" flag.
             if (status.Mode == SyncMode.Spawn) status.Mode = SyncMode.Default;
@@ -80,16 +64,10 @@ public class SyncServer : Sync
         var packet = new SyncPacket();
         foreach (var status in StatusByObject.Values) {
             var values = new List<(byte, object)>();
-            foreach (var prop in status.Info.PropertiesByID)
-                values.Add((prop.ID, prop.Getter(status.Object)));
+            for (byte i = 0; i < status.Info.PropertiesByID.Count; i++)
+                values.Add((i, status.Info.PropertiesByID[i].Get(status.Object)));
             packet.Changes.Add(new SyncPacket.Object(status.Info.ID, status.ID, SyncMode.Spawn, values));
         }
         NetworkPackets.Send(server, new []{ networkID }, packet);
     }
-
-    public override void Clear()
-    {
-        base.Clear();
-        _dirtyObjects.Clear();
-    }
 }
diff --git a/src/Objects/Block.cs b/src/Objects/Block.cs
index dcf060e..5c0a4ee 100644
--- a/src/Objects/Block.cs
+++ b/src/Objects/Block.cs
@@ -1,15 +1,15 @@
 using Godot;
 
-[Sync]
+[Spawn, Sync, Save]
 public class Block : StaticBody2D
 {
-    [Sync]
+    [Sync, Save]
     public new BlockPos Position {
         get => BlockPos.FromVector(base.Position);
         set => base.Position = this.SetSync(value).ToVector();
     }
 
-    [Sync]
+    [Sync, Save]
     public Color Color {
         get => Modulate;
         set => Modulate = this.SetSync(value);
diff --git a/src/Objects/ObjectHolder.cs b/src/Objects/ObjectHolder.cs
index cdb2720..8f1c771 100644
--- a/src/Objects/ObjectHolder.cs
+++ b/src/Objects/ObjectHolder.cs
@@ -1,39 +1,67 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
+using System.Linq;
 using Godot;
 
-public class ObjectHolder
+public class ObjectHolder : IReadOnlyCollection<(UniqueID, Node)>
 {
     private readonly Dictionary<UniqueID, Node> _nodeByID = new Dictionary<UniqueID, Node>();
     private readonly Dictionary<Node, UniqueID> _idByNode = new Dictionary<Node, UniqueID>();
     private uint _newIDCounter = 1;
 
-    public UniqueID Add(Node obj)
-    {
-        UniqueID id;
-        // Keep going until we find an unused UniqueID.
-        while (_nodeByID.TryGetValue(id = new UniqueID(_newIDCounter++), out _)) {  }
-        Add(id, obj);
-        return id;
-    }
-    public void Add(UniqueID id, Node obj)
-    {
-        _nodeByID.Add(id, obj);
-        _idByNode.Add(obj, id);
-    }
+    public event Action<UniqueID, Node> Added;
+    public event Action<UniqueID, Node> Removed;
+    public event Action Cleared;
+
 
     public UniqueID GetSyncID(Node obj)
         => _idByNode.TryGetValue(obj, out var value) ? value : throw new Exception(
             $"The specified object '{obj}' does not have a UniqueID");
-    public Node GetNodeByID(UniqueID id)
+    public Node GetObjectByID(UniqueID id)
         => _nodeByID.TryGetValue(id, out var value) ? value : throw new Exception(
             $"No object associated with {id}");
 
+
+    internal void Add(UniqueID? id, Node obj)
+    {
+        if (!(id is UniqueID uid)) {
+            // If the given UniqueID is null, keep going until we find an unused one.
+            while (_nodeByID.ContainsKey(uid = new UniqueID(_newIDCounter++))) {  }
+        }
+
+        _nodeByID.Add(uid, obj);
+        _idByNode.Add(obj, uid);
+        Added?.Invoke(uid, obj);
+    }
+
+    internal void OnNodeRemoved(Node obj)
+    {
+        if (!_idByNode.TryGetValue(obj, out var id)) return;
+
+        _nodeByID.Remove(id);
+        _idByNode.Remove(obj);
+        Removed?.Invoke(id, obj);
+    }
+
     public void Clear()
     {
+        var objects = _nodeByID.Values.ToArray();
+
         _nodeByID.Clear();
         _idByNode.Clear();
+        Cleared?.Invoke();
+
+        foreach (var obj in objects)
+            obj.RemoveFromParent();
     }
+
+    // IReadOnlyCollection implementation
+    public int Count => _nodeByID.Count;
+    public IEnumerator<(UniqueID, Node)> GetEnumerator()
+        => _nodeByID.Select(entry => (entry.Key, entry.Value)).GetEnumerator();
+    IEnumerator IEnumerable.GetEnumerator()
+        => GetEnumerator();
 }
 
 public readonly struct UniqueID : IEquatable<UniqueID>
diff --git a/src/Objects/Player.cs b/src/Objects/Player.cs
index cb0edab..6f5f0c9 100644
--- a/src/Objects/Player.cs
+++ b/src/Objects/Player.cs
@@ -2,7 +2,7 @@ using System;
 using Godot;
 
 // TODO: Maybe figure out how we can make different classes (LocalPlayer, NPCPlayer) synchronizable.
-[Sync]
+[Spawn, Sync]
 public class Player : KinematicBody2D, IInitializer
 {
     [Export] public NodePath DisplayNamePath { get; set; }
@@ -101,7 +101,7 @@ public class Player : KinematicBody2D, IInitializer
     }
 
     [RPC(PacketDirection.ServerToClient)]
-    private void ResetPosition(Vector2 position)
+    public void ResetPosition(Vector2 position)
     {
         base.Position = position;
         Velocity      = Vector2.Zero;
diff --git a/src/Objects/SpawnRegistry.cs b/src/Objects/SpawnRegistry.cs
new file mode 100644
index 0000000..4b2c675
--- /dev/null
+++ b/src/Objects/SpawnRegistry.cs
@@ -0,0 +1,70 @@
+using System;
+using System.Collections.Generic;
+using System.Reflection;
+using Godot;
+
+public static class SpawnRegistry
+{
+    private static readonly Dictionary<int, SpawnInfo> _byID = new Dictionary<int, SpawnInfo>();
+    private static readonly Dictionary<Type, SpawnInfo> _byType = new Dictionary<Type, SpawnInfo>();
+
+    static SpawnRegistry()
+    {
+        foreach (var type in typeof(SpawnRegistry).Assembly.GetTypes()) {
+            var objAttr = type.GetCustomAttribute<SpawnAttribute>();
+            if (objAttr == null) continue;
+
+            if (!typeof(Node).IsAssignableFrom(type)) throw new Exception(
+                $"Type {type} with {nameof(SpawnAttribute)} must be a subclass of {nameof(Node)}");
+
+            var objInfo = new SpawnInfo(type);
+            _byID.Add(objInfo.HashID, objInfo);
+            _byType.Add(objInfo.Type, objInfo);
+        }
+    }
+
+    public static T Spawn<T>(this Server server)
+        where T : Node
+    {
+        var info = Get<T>();
+        var obj  = info.Scene.Init<T>();
+        server.GetNode("World").AddChild(obj, true);
+        server.Objects.Add(null, obj);
+        return obj;
+    }
+
+    public static SpawnInfo Get(int id)
+        => _byID.TryGetValue(id, out var value) ? value : throw new Exception(
+            $"No {nameof(SpawnInfo)} found with ID {id}");
+
+    public static SpawnInfo Get<T>()
+        => Get(typeof(T));
+    public static SpawnInfo Get(Type type)
+        => _byType.TryGetValue(type, out var value) ? value : throw new Exception(
+            $"No {nameof(SpawnInfo)} found for type {type} (missing {nameof(SpawnAttribute)}?)");
+}
+
+public class SpawnInfo
+{
+    public Type Type { get; }
+    public int HashID { get; }
+    public PackedScene Scene { get; }
+
+    public SpawnInfo(Type type)
+    {
+        Type   = type;
+        HashID = type.FullName.GetDeterministicHashCode();
+
+        var sceneStr = Type.GetCustomAttribute<SpawnAttribute>().Scene;
+        if (sceneStr == null) sceneStr = $"res://scene/{Type.Name}.tscn";
+        Scene = GD.Load<PackedScene>(sceneStr);
+    }
+}
+
+[AttributeUsage(AttributeTargets.Class)]
+public class SpawnAttribute : Attribute
+{
+    public string Scene { get; }
+    public SpawnAttribute(string scene = null)
+        => Scene = scene;
+}
diff --git a/src/Scenes/Game.cs b/src/Scenes/Game.cs
index 9bd383c..abc6185 100644
--- a/src/Scenes/Game.cs
+++ b/src/Scenes/Game.cs
@@ -4,9 +4,14 @@ using Godot.Collections;
 
 public abstract class Game : Node2D
 {
-    public ObjectHolder Objects { get; } = new ObjectHolder();
+    public ObjectHolder Objects { get; }
     public Sync Sync { get; protected set; }
 
+    public Game() => Objects = new ObjectHolder();
+
+    public override void _Ready() => GetTree().Connect("node_removed", this, nameof(OnNodeRemoved));
+    private void OnNodeRemoved(Node node) => Objects.OnNodeRemoved(node);
+
 	// Using _EnterTree to make sure this code runs before any other.
 	public override void _EnterTree()
 		=> GD.Randomize();
diff --git a/src/Scenes/Server.cs b/src/Scenes/Server.cs
index b20f75b..35081c3 100644
--- a/src/Scenes/Server.cs
+++ b/src/Scenes/Server.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using Godot;
 
 // TODO: Allow for initially private integrated server to open itself up to the public.
@@ -79,6 +80,8 @@ public class Server : Game
     }
 
 
+    public IEnumerable<(NetworkID, Player)> Players
+        => _playersByNetworkID.Select(entry => (entry.Key, entry.Value));
     public Player GetPlayer(NetworkID networkID)
         => _playersByNetworkID[networkID];
     public NetworkID GetNetworkID(Player player)
@@ -107,7 +110,7 @@ public class Server : Game
             _networkIDByPlayer[player] = networkID;
         } else {
             Sync.SendAllObjects(this, networkID);
-            player = Sync.Spawn<Player>();
+            player = this.Spawn<Player>();
             player.Position = Vector2.Zero;
             player.Color    = Colors.Red;
 
@@ -127,7 +130,7 @@ public class Server : Game
         // Local player stays around for reconnecting.
         if (_localPlayer == player) return;
 
-        Sync.Destroy(player);
+        player.RemoveFromParent();
         _playersByNetworkID.Remove(networkID);
         _networkIDByPlayer.Remove(player);
     }
diff --git a/src/Utility/Extensions.cs b/src/Utility/Extensions.cs
index 84441ee..670a6fb 100644
--- a/src/Utility/Extensions.cs
+++ b/src/Utility/Extensions.cs
@@ -4,6 +4,21 @@ using Godot;
 
 public static class Extensions
 {
+    public static void RemoveFromParent(this Node node)
+    {
+        node.GetParent().RemoveChild(node);
+        node.QueueFree();
+    }
+
+    public static T Init<T>(this PackedScene @this)
+        where T : Node
+    {
+        var instance = (T)@this.Instance();
+        (instance as IInitializer)?.Initialize();
+        return instance;
+    }
+
+
     public static Game GetGame(this Node node)
         => node.GetTree().Root.GetChild<Game>(0);
     public static Client GetClient(this Node node)
@@ -11,23 +26,30 @@ public static class Extensions
     public static Server GetServer(this Node node)
         => node.GetGame() as Server;
 
+
     public static TValue SetSync<TObject, TValue>(
         this TObject obj, TValue value,
         [CallerMemberName] string property = null)
             where TObject : Node
         { obj.GetServer()?.Sync.MarkDirty(obj, property); return value; }
 
-    public static T Init<T>(this PackedScene @this)
-        where T : Node
-    {
-        var instance = (T)@this.Instance();
-        (instance as IInitializer)?.Initialize();
-        return instance;
-    }
 
     public static void Deconstruct<TKey, TValue>(
             this KeyValuePair<TKey, TValue> kvp, out TKey key, out TValue value)
         { key = kvp.Key; value = kvp.Value; }
+
+    public static int GetDeterministicHashCode(this string str)
+    { unchecked {
+        int hash1 = (5381 << 16) + 5381;
+        int hash2 = hash1;
+        for (int i = 0; i < str.Length; i += 2) {
+            hash1 = ((hash1 << 5) + hash1) ^ str[i];
+            if (i == str.Length - 1) break;
+            hash2 = ((hash2 << 5) + hash2) ^ str[i + 1];
+        }
+        return hash1 + (hash2 * 1566083941);
+    } }
+
 }
 
 public interface IInitializer
diff --git a/ui_theme.tres b/ui_theme.tres
index 62a7a75..b7ce4d9 100644
--- a/ui_theme.tres
+++ b/ui_theme.tres
@@ -4,7 +4,7 @@
 
 [sub_resource type="DynamicFont" id=1]
 outline_size = 1
-outline_color = Color( 0, 0, 0, 1 )
+outline_color = Color( 0, 0, 0, 0.5 )
 extra_spacing_top = -3
 extra_spacing_bottom = -1
 font_data = ExtResource( 1 )