diff --git a/PolyMod.csproj b/PolyMod.csproj
index a6734ef..2c165a4 100644
--- a/PolyMod.csproj
+++ b/PolyMod.csproj
@@ -11,7 +11,7 @@
         </RestoreAdditionalProjectSources>
         <Configurations>IL2CPP</Configurations>
         <RootNamespace>PolyMod</RootNamespace>
-        <Version>1.2.17</Version>
+        <Version>1.3.0-pre</Version>
         <PolytopiaVersion>2.17.2.16299</PolytopiaVersion>
         <Authors>PolyModdingTeam</Authors>
         <Description>The Battle of Polytopia's mod loader.</Description>
diff --git a/src/Multiplayer/Client.cs b/src/Multiplayer/Client.cs
new file mode 100644
index 0000000..add1b28
--- /dev/null
+++ b/src/Multiplayer/Client.cs
@@ -0,0 +1,374 @@
+using HarmonyLib;
+using Il2CppMicrosoft.AspNetCore.SignalR.Client;
+using PolyMod.Multiplayer.ViewModels;
+using Polytopia.Data;
+using PolytopiaBackendBase;
+using PolytopiaBackendBase.Common;
+using PolytopiaBackendBase.Game;
+using PolytopiaBackendBase.Game.BindingModels;
+using UnityEngine;
+using Newtonsoft.Json;
+
+namespace PolyMod.Multiplayer;
+
+public static class Client
+{
+    internal const string DEFAULT_SERVER_URL = "https://dev.polydystopia.xyz";
+    internal const string LOCAL_SERVER_URL = "http://localhost:5051/";
+    private const string GldMarker = "##GLD:";
+    internal static bool allowGldMods = false;
+
+    // Cache parsed GLD by game Seed to handle rewinds/reloads
+    private static readonly Dictionary<int, GameLogicData> _gldCache = new();
+    private static readonly Dictionary<int, int> _versionCache = new(); // Seed -> modGldVersion
+
+    internal static void Init()
+    {
+        Harmony.CreateAndPatchAll(typeof(Client));
+        BuildConfig buildConfig = BuildConfigHelper.GetSelectedBuildConfig();
+        buildConfig.buildServerURL = BuildServerURL.Custom;
+        buildConfig.customServerURL = LOCAL_SERVER_URL;
+
+        Plugin.logger.LogInfo($"Multiplayer> Server URL set to: {Plugin.config.backendUrl}");
+        Plugin.logger.LogInfo("Multiplayer> GLD patches applied");
+    }
+
+    [HarmonyPostfix]
+    [HarmonyPatch(typeof(MultiplayerSelectionScreen), nameof(MultiplayerSelectionScreen.Show))]
+    public static void MultiplayerScreen_Show(MultiplayerSelectionScreen __instance)
+    {
+        __instance.TournamentsButton.gameObject.SetActive(false);
+    }
+
+    [HarmonyPostfix]
+    [HarmonyPatch(typeof(StartScreen_UI2), nameof(StartScreen_UI2.RunLayout))]
+    private static void StartScreen_UI2_RunLayout(StartScreen_UI2 __instance)
+    {
+        __instance.highscoreButton.gameObject.SetActive(false);
+        __instance.weeklyChallengeButton.gameObject.SetActive(false);
+    }
+
+    [HarmonyPostfix]
+    [HarmonyPatch(typeof(SystemInfo), nameof(SystemInfo.deviceUniqueIdentifier), MethodType.Getter)]
+    public static void SteamClient_get_SteamId(ref string  __result)
+    {
+        if (Plugin.config.overrideDeviceId != string.Empty)
+        {
+            __result = Plugin.config.overrideDeviceId;
+        }
+    }
+
+
+    [HarmonyPrefix]
+    [HarmonyPatch(typeof(ClientBase), nameof(ClientBase.SendCommand))]
+    private static bool ClientBase_SendCommand(
+        ClientBase __instance,
+        CommandBase command)
+    {
+
+        Plugin.logger.LogInfo("Multiplayer> ClientBase_SendCommand");
+        Il2CppSystem.Threading.Tasks.Task<ServerResponse<BoolResponseViewModel>> task = new();
+        var taskCompletionSource = new Il2CppSystem.Threading.Tasks.TaskCompletionSource<ServerResponse<BoolResponseViewModel>>();
+
+        _ = ClientBase_SendCommand_Async(taskCompletionSource, __instance, command);
+
+        task = taskCompletionSource.Task;
+
+        return false;
+    }
+
+    private static async System.Threading.Tasks.Task ClientBase_SendCommand_Async(
+        Il2CppSystem.Threading.Tasks.TaskCompletionSource<ServerResponse<BoolResponseViewModel>> tcs,
+        ClientBase client,
+        CommandBase command)
+    {
+        try
+        {
+            if (!client.CurrentGameId.HasValue)
+            {
+                Console.Write("Tried to perform and send command but no GameId was set");
+                return;
+            }
+            if (!ClientActionManager.CanReceiveCommand(command, client.GameState))
+            {
+                Console.Write("Tried to send invalid command");
+                return;
+            }
+            uint currentResetId = client.resets;
+            int count = client.GameState.CommandStack.Count;
+            var list = new Il2CppSystem.Collections.Generic.List<CommandBase>();
+            list.Add(command);
+            client.ActionManager.ExecuteCommands(list);
+            await client.SendCommandToServer(command, count);
+
+            var serializedGameState = SerializationHelpers.ToByteArray(client.GameState, client.GameState.Version);
+
+            var succ = GameStateSummary.FromGameStateByteArray(serializedGameState,
+                out GameStateSummary stateSummary, out var gameState);
+
+            var serializedGameSummary = SerializationHelpers.ToByteArray(stateSummary, gameState.Version);
+
+
+            client.GameState.TryGetPlayer(client.GameState.CurrentPlayer, out PlayerState playerState);
+            var currentPlayerId = "";
+            if(playerState.AccountId.HasValue)
+            {
+                currentPlayerId = playerState.AccountId.Value.ToString();
+            }
+            var setupGameDataViewModel = new ModdedGameStateViewModel
+            {
+                gameId = client.gameId.ToString(),
+                serializedGameState = serializedGameState,
+                serializedGameSummary = serializedGameSummary,
+                gameSettingsJson = "",
+                currentPlayerId = currentPlayerId,
+                IsEndTurnCommand = command.GetCommandType() == CommandType.EndTurn
+            };
+
+
+
+            var setupData = System.Text.Json.JsonSerializer.Serialize(setupGameDataViewModel);
+
+            var serverResponse = await PolytopiaBackendAdapter.Instance.HubConnection.InvokeAsync<ServerResponse<BoolResponseViewModel>>(
+                "UpdateGameStateModded",
+                setupData,
+                Il2CppSystem.Threading.CancellationToken.None
+            );
+            tcs.SetResult(serverResponse);
+        }
+        catch (Exception ex)
+        {
+            Plugin.logger.LogError("Multiplayer> Error during HandleSendCommandModded: " + ex.Message);
+            tcs.SetException(new Il2CppSystem.Exception(ex.Message));
+        }
+    }
+
+    [HarmonyPrefix]
+    [HarmonyPatch(typeof(BackendAdapter), nameof(BackendAdapter.StartLobbyGame))]
+    private static bool BackendAdapter_StartLobbyGame_Modded(
+        ref Il2CppSystem.Threading.Tasks.Task<ServerResponse<LobbyGameViewModel>> __result,
+        BackendAdapter __instance,
+        StartLobbyBindingModel model)
+    {
+        Plugin.logger.LogInfo("Multiplayer> BackendAdapter_StartLobbyGame_Modded");
+        var taskCompletionSource = new Il2CppSystem.Threading.Tasks.TaskCompletionSource<ServerResponse<LobbyGameViewModel>>();
+
+        _ = BackendAdapter_StartLobbyGame_Async(taskCompletionSource, __instance, model);
+
+        __result = taskCompletionSource.Task;
+
+        return false;
+    }
+
+    private static async System.Threading.Tasks.Task BackendAdapter_StartLobbyGame_Async(
+        Il2CppSystem.Threading.Tasks.TaskCompletionSource<ServerResponse<LobbyGameViewModel>> tcs,
+        BackendAdapter instance,
+        StartLobbyBindingModel model)
+    {
+        try
+        {
+            var lobbyResponse = await PolytopiaBackendAdapter.Instance.GetLobby(new GetLobbyBindingModel
+            {
+                LobbyId = model.LobbyId
+            });
+
+            Plugin.logger.LogInfo($"Multiplayer> Lobby processed {lobbyResponse.Success}");
+            LobbyGameViewModel lobbyGameViewModel = lobbyResponse.Data;
+            Plugin.logger.LogInfo("Multiplayer> Lobby received");
+
+            (byte[] serializedGameState, string gameSettingsJson) = CreateMultiplayerGame(
+                lobbyGameViewModel,
+                VersionManager.GameVersion,
+                VersionManager.GameLogicDataVersion
+            );
+
+            Plugin.logger.LogInfo("Multiplayer> GameState and Settiings created");
+
+            var succ = GameStateSummary.FromGameStateByteArray(serializedGameState,
+                out GameStateSummary stateSummary, out var gameState);
+
+            var serializedGameSummary = SerializationHelpers.ToByteArray(stateSummary, gameState.Version);
+            var setupGameDataViewModel = new ModdedGameStateViewModel
+            {
+                lobbyId = lobbyGameViewModel.Id.ToString(),
+                serializedGameState = serializedGameState,
+                serializedGameSummary = serializedGameSummary,
+                gameSettingsJson = gameSettingsJson
+            };
+
+            var setupData = System.Text.Json.JsonSerializer.Serialize(setupGameDataViewModel);
+
+            var serverResponse = await instance.HubConnection.InvokeAsync<ServerResponse<LobbyGameViewModel>>(
+                "StartLobbyGameModded",
+                setupData,
+                Il2CppSystem.Threading.CancellationToken.None
+            );
+            Plugin.logger.LogInfo("Multiplayer> Invoked StartLobbyGameModded");
+            tcs.SetResult(serverResponse);
+        }
+        catch (Exception ex)
+        {
+            Plugin.logger.LogError("Multiplayer> Error during HandleStartLobbyGameModded: " + ex.Message);
+            tcs.SetException(new Il2CppSystem.Exception(ex.Message));
+        }
+    }
+
+    public static (byte[] serializedGameState, string gameSettingsJson) CreateMultiplayerGame(LobbyGameViewModel lobby,
+        int gameVersion, int gameLogicVersion)
+    {
+        var lobbyMapSize = lobby.MapSize;
+        var settings = new GameSettings();
+        settings.ApplyLobbySettings(lobby);
+        if (settings.LiveGamePreset)
+        {
+            settings.SetLiveModePreset();
+        }
+        foreach (var participatorViewModel in lobby.Participators)
+        {
+            var humanPlayer = new PlayerData
+            {
+                type = PlayerDataType.LocalUser,
+                state = PlayerDataFriendshipState.Accepted,
+                knownTribe = true,
+                tribe = (TribeType)participatorViewModel.SelectedTribe,
+                tribeMix = TribeType.None, // TribeMix is byte too
+                skinType = (SkinType)participatorViewModel.SelectedTribeSkin,
+                defaultName = participatorViewModel.GetNameInternal()
+            };
+            humanPlayer.profile.id = participatorViewModel.UserId;
+            humanPlayer.profile.SetName(participatorViewModel.GetNameInternal());
+            SerializationHelpers.FromByteArray<AvatarState>(participatorViewModel.AvatarStateData, out var avatarState);
+            humanPlayer.profile.avatarState = avatarState;
+
+            settings.AddPlayer(humanPlayer);
+        }
+
+        foreach (var botDifficulty in lobby.Bots)
+        {
+            var botGuid = Il2CppSystem.Guid.NewGuid();
+
+            var botPlayer = new PlayerData
+            {
+                type = PlayerDataType.Bot,
+                state = PlayerDataFriendshipState.Accepted,
+                knownTribe = true,
+                tribe = Enum.GetValues<TribeType>().Where(t => t != TribeType.None)
+                    .OrderBy(x => Il2CppSystem.Guid.NewGuid()).First()
+            };
+            ;
+            botPlayer.botDifficulty = (BotDifficulty)botDifficulty;
+            botPlayer.skinType = SkinType.Default;
+            botPlayer.defaultName = "Bot" + botGuid;
+            botPlayer.profile.id = botGuid;
+
+            settings.AddPlayer(botPlayer);
+        }
+
+        GameState gameState = new GameState()
+        {
+            Version = gameVersion,
+            Settings = settings,
+            PlayerStates = new Il2CppSystem.Collections.Generic.List<PlayerState>()
+        };
+
+        for (int index = 0; index < settings.GetPlayerCount(); ++index)
+        {
+            PlayerData player = settings.GetPlayer(index);
+            if (player.type != PlayerDataType.Bot)
+            {
+                var nullableGuid = new Il2CppSystem.Nullable<Il2CppSystem.Guid>(player.profile.id);
+                if (!nullableGuid.HasValue)
+                {
+                    throw new Exception("GUID was not set properly!");
+                }
+                PlayerState playerState = new PlayerState()
+                {
+                    Id = (byte)(index + 1),
+                    AccountId = nullableGuid,
+                    AutoPlay = player.type == PlayerDataType.Bot,
+                    UserName = player.GetNameInternal(),
+                    tribe = player.tribe,
+                    tribeMix = player.tribeMix,
+                    hasChosenTribe = true,
+                    skinType = player.skinType
+                };
+                gameState.PlayerStates.Add(playerState);
+                Plugin.logger.LogInfo($"Multiplayer> Created player: {playerState}");
+            }
+            else
+            {
+                GameStateUtils.AddAIOpponent(gameState, GameStateUtils.GetRandomPickableTribe(gameState),
+                    GameSettings.HandicapFromDifficulty(player.botDifficulty), player.skinType);
+            }
+        }
+
+        GameStateUtils.SetPlayerColors(gameState);
+        GameStateUtils.AddNaturePlayer(gameState);
+
+        Plugin.logger.LogInfo("Multiplayer> Creating world...");
+
+        ushort num = (ushort)Math.Max(lobbyMapSize,
+            (int)MapDataExtensions.GetMinimumMapSize(gameState.PlayerCount));
+        gameState.Map = new MapData(num, num);
+        MapGeneratorSettings generatorSettings = settings.GetMapGeneratorSettings();
+        new MapGenerator().Generate(gameState, generatorSettings);
+
+        Plugin.logger.LogInfo($"Multiplayer> Creating initial state for {gameState.PlayerCount} players...");
+
+        foreach (PlayerState player in gameState.PlayerStates)
+        {
+            foreach (PlayerState otherPlayer in gameState.PlayerStates)
+                player.aggressions[otherPlayer.Id] = 0;
+
+            if (player.Id != byte.MaxValue && gameState.GameLogicData.TryGetData(player.tribe, out TribeData tribeData))
+            {
+                player.Currency = tribeData.startingStars;
+                TileData tile = gameState.Map.GetTile(player.startTile);
+                UnitState unitState = ActionUtils.TrainUnitScored(gameState, player, tile, tribeData.startingUnit);
+                unitState.attacked = false;
+                unitState.moved = false;
+            }
+        }
+
+        Plugin.logger.LogInfo("Multiplayer> Session created successfully");
+
+        gameState.CommandStack.Add((CommandBase)new StartMatchCommand((byte)1));
+
+        var serializedGameState = SerializationHelpers.ToByteArray(gameState, gameState.Version);
+
+        return (serializedGameState,
+            JsonConvert.SerializeObject(gameState.Settings));
+    }
+
+    // FIX FOR NATURE PLAYER. BOTS ARENT IMPLEMENTED YET
+
+    [HarmonyPrefix]
+    [HarmonyPatch(typeof(GameState), nameof(GameState.EndPlayerTurn))]
+	private static bool GameState_EndPlayerTurn(GameState __instance, bool newTurn = false)
+	{
+        Console.Write("GameState_EndPlayerTurn");
+		__instance.CurrentPlayerIndex++;
+		if (__instance.CurrentPlayerIndex >=__instance. PlayerStates.Count)
+		{
+			__instance.CurrentPlayerIndex = 0;
+			newTurn = true;
+		}
+
+        var currentPlayer = __instance.PlayerStates[__instance.CurrentPlayerIndex];
+		if (!currentPlayer.IsAlive(__instance))
+		{
+			__instance.EndPlayerTurn(newTurn);
+		}
+		else if (newTurn)
+		{
+			__instance.CurrentTurn++;
+		}
+
+        if(currentPlayer.AutoPlay)
+        {
+            __instance.CommandStack.Add(new EndTurnCommand(currentPlayer.Id));
+        }
+        Console.Write("finished");
+        return false;
+	}
+}
diff --git a/src/Multiplayer/SerializationUtils.cs b/src/Multiplayer/SerializationUtils.cs
new file mode 100644
index 0000000..e91a46b
--- /dev/null
+++ b/src/Multiplayer/SerializationUtils.cs
@@ -0,0 +1,74 @@
+using HarmonyLib;
+using Polytopia.Data;
+using PolytopiaBackendBase.Common;
+
+namespace PolyMod.Multiplayer;
+
+public static class SerializationUtils
+{
+    internal static void Init()
+    {
+        Harmony.CreateAndPatchAll(typeof(SerializationUtils));
+    }
+
+    [HarmonyPrefix]
+    [HarmonyPatch(typeof(GamePlayerSummary), nameof(GamePlayerSummary.Serialize))]
+	public static bool GamePlayerSummary_Serialize(GamePlayerSummary __instance, Il2CppSystem.IO.BinaryWriter writer, int version)
+	{
+        Plugin.logger.LogInfo("Multiplayer> GamePlayerSummary_Serialize");
+		var memoryStream = new Il2CppSystem.IO.MemoryStream();
+		var binaryWriter = new Il2CppSystem.IO.BinaryWriter(memoryStream);
+		binaryWriter.Write(__instance.Id);
+		binaryWriter.Write(__instance.PolytopiaId.ToString());
+		binaryWriter.Write(__instance.UserName ?? "");
+		binaryWriter.Write((int)__instance.TribeType);
+		binaryWriter.Write(__instance.AutoPlay);
+		binaryWriter.Write(__instance.HasChosenTribe);
+		binaryWriter.Write(__instance.Handicap);
+		binaryWriter.Write(__instance.IsDead);
+		if (version >= 86)
+		{
+			binaryWriter.Write((int)__instance.SkinType);
+		}
+		writer.Write((int)memoryStream.Length);
+		memoryStream.WriteTo(writer.BaseStream);
+        return false;
+	}
+
+    [HarmonyPrefix]
+    [HarmonyPatch(typeof(GamePlayerSummary), nameof(GamePlayerSummary.Deserialize))]
+	public static bool GamePlayerSummary_Deserialize(GamePlayerSummary __instance, Il2CppSystem.IO.BinaryReader reader, int version)
+	{
+        Plugin.logger.LogInfo("Multiplayer> GamePlayerSummary_Deserialize");
+		int num = reader.ReadInt32();
+		long position = reader.BaseStream.Position;
+		__instance.Id = reader.ReadByte();
+		string g = reader.ReadString();
+        Il2CppSystem.Guid parsed;
+        Il2CppSystem.Nullable<Il2CppSystem.Guid> nullableGuid;
+        if (Il2CppSystem.Guid.TryParse(g, out parsed))
+            nullableGuid = new Il2CppSystem.Nullable<Il2CppSystem.Guid>(parsed);
+        else
+            nullableGuid = new Il2CppSystem.Nullable<Il2CppSystem.Guid>();
+        __instance.PolytopiaId = nullableGuid;
+		__instance.UserName = reader.ReadString();
+		__instance.TribeType = (TribeType)reader.ReadInt32();
+		__instance.AutoPlay = reader.ReadBoolean();
+		__instance.HasChosenTribe = reader.ReadBoolean();
+		__instance.Handicap = reader.ReadInt32();
+		__instance.IsDead = reader.ReadBoolean();
+		if (version >= 86)
+		{
+			__instance.SkinType = (SkinType)reader.ReadInt32();
+		}
+		reader.BaseStream.Position = position + num;
+        return false;
+	}
+
+    [HarmonyPostfix]
+    [HarmonyPatch(typeof(PlayerState), nameof(PlayerState.Deserialize))]
+	public static void PlayerState_Deserialize(PlayerState __instance, Il2CppSystem.IO.BinaryReader reader, int version)
+	{
+		__instance.climate = __instance.tribe;
+	}
+}
\ No newline at end of file
diff --git a/src/Multiplayer/ViewModels/ModdedGameStateViewModel.cs b/src/Multiplayer/ViewModels/ModdedGameStateViewModel.cs
new file mode 100644
index 0000000..176a997
--- /dev/null
+++ b/src/Multiplayer/ViewModels/ModdedGameStateViewModel.cs
@@ -0,0 +1,13 @@
+namespace PolyMod.Multiplayer.ViewModels;
+public class ModdedGameStateViewModel
+{
+	public string gameId { get; set; } = "";
+    public string lobbyId { get; set; } = "";
+
+	public byte[] serializedGameState { get; set; } = new byte[0];
+	public byte[] serializedGameSummary { get; set; } = new byte[0];
+
+	public string gameSettingsJson { get; set; } = "";
+	public string currentPlayerId { get; set; } = "";
+	public bool IsEndTurnCommand { get; set; } = false;
+}
\ No newline at end of file
diff --git a/src/Plugin.cs b/src/Plugin.cs
index 96ae942..597609c 100644
--- a/src/Plugin.cs
+++ b/src/Plugin.cs
@@ -24,7 +24,9 @@ internal record PolyConfig(
 		bool debug = false,
 		bool autoUpdate = true,
 		bool updatePrerelease = false,
-		bool allowUnsafeIndexes = false
+		bool allowUnsafeIndexes = false,
+		string backendUrl = Multiplayer.Client.DEFAULT_SERVER_URL,
+		string overrideDeviceId = ""
 	);
 
 	/// <summary>
@@ -132,6 +134,8 @@ public override void Load()
 		Hub.Init();
 
 		Main.Init();
+		Multiplayer.SerializationUtils.Init();
+		Multiplayer.Client.Init();
 	}
 
 	/// <summary>