diff --git a/Theriapolis.Godot/Main.cs b/Theriapolis.Godot/Main.cs
index b6c895c..7edb69b 100644
--- a/Theriapolis.Godot/Main.cs
+++ b/Theriapolis.Godot/Main.cs
@@ -6,6 +6,27 @@ public partial class Main : Node
 {
     public override void _Ready()
     {
+        var args = OS.GetCmdlineUserArgs();
+        ulong? smokeTestSeed = null;
+        for (int i = 0; i < args.Length; i++)
+        {
+            if (args[i] == "--smoke-test")
+            {
+                ulong seed = 12345UL;
+                if (i + 1 < args.Length && ulong.TryParse(args[i + 1], out var parsed))
+                    seed = parsed;
+                smokeTestSeed = seed;
+                break;
+            }
+        }
+
+        if (smokeTestSeed.HasValue)
+        {
+            int code = SmokeTest.Run(smokeTestSeed.Value);
+            GetTree().Quit(code);
+            return;
+        }
+
         GD.Print("Theriapolis.Godot host ready (M0 hello-world).");
     }
 
diff --git a/Theriapolis.Godot/SmokeTest.cs b/Theriapolis.Godot/SmokeTest.cs
new file mode 100644
index 0000000..4a707ed
--- /dev/null
+++ b/Theriapolis.Godot/SmokeTest.cs
@@ -0,0 +1,59 @@
+using Godot;
+using System.IO;
+using System.Linq;
+using Theriapolis.Core.World.Generation;
+
+namespace Theriapolis.GodotHost;
+
+/// <summary>
+/// M1 determinism oracle. Runs the full Core worldgen pipeline from inside
+/// the Godot process and prints FNV hashes. Output must match
+/// <c>dotnet run --project Theriapolis.Tools -- worldgen-hash --seed N</c>
+/// byte-for-byte. This proves Core works untouched under Godot's csproj.
+/// </summary>
+public static class SmokeTest
+{
+    public static int Run(ulong seed)
+    {
+        string dataDir = ResolveDataDir();
+        if (!Directory.Exists(dataDir))
+        {
+            GD.PrintErr($"[smoke-test] Data directory not found: {dataDir}");
+            return 1;
+        }
+
+        GD.Print($"[smoke-test] seed=0x{seed:X} data-dir={dataDir}");
+        var ctx = new WorldGenContext(seed, dataDir);
+        WorldGenerator.RunAll(ctx);
+        var w = ctx.World;
+
+        GD.Print($"[smoke-test] === FNV hashes ===");
+        GD.Print($"[smoke-test] elevation     = 0x{w.HashElevation():X16}");
+        GD.Print($"[smoke-test] moisture      = 0x{w.HashMoisture():X16}");
+        GD.Print($"[smoke-test] temperature   = 0x{w.HashTemperature():X16}");
+        GD.Print($"[smoke-test] biomes        = 0x{w.HashBiomes():X16}");
+        GD.Print($"[smoke-test] settlements   = 0x{w.HashSettlements():X16}");
+        GD.Print($"[smoke-test] polylines     = 0x{w.HashPolylines():X16}");
+        GD.Print($"[smoke-test] === Per-stage hashes ({w.StageHashes.Count}) ===");
+        foreach (var kv in w.StageHashes.OrderBy(k => k.Key, System.StringComparer.Ordinal))
+            GD.Print($"[smoke-test] {kv.Key,-32} = 0x{kv.Value:X16}");
+        return 0;
+    }
+
+    private static string ResolveDataDir()
+    {
+        string fromRes = ProjectSettings.GlobalizePath("res://../Content/Data");
+        if (Directory.Exists(fromRes)) return fromRes;
+
+        string? dir = ProjectSettings.GlobalizePath("res://").TrimEnd('/', '\\');
+        for (int i = 0; i < 6; i++)
+        {
+            if (string.IsNullOrEmpty(dir)) break;
+            string candidate = Path.Combine(dir, "Content", "Data");
+            if (Directory.Exists(candidate)) return candidate;
+            dir = Path.GetDirectoryName(dir);
+        }
+
+        return fromRes;
+    }
+}
diff --git a/Theriapolis.Tests/Architecture/CoreNoDependencyTests.cs b/Theriapolis.Tests/Architecture/CoreNoDependencyTests.cs
index 24b7d9e..a69133c 100644
--- a/Theriapolis.Tests/Architecture/CoreNoDependencyTests.cs
+++ b/Theriapolis.Tests/Architecture/CoreNoDependencyTests.cs
@@ -4,9 +4,11 @@ using Xunit;
 namespace Theriapolis.Tests.Architecture;
 
 /// <summary>
-/// Hard rule #1: Theriapolis.Core must not reference MonoGame or Microsoft.Xna.
+/// Hard rule #1: Theriapolis.Core must not reference any rendering engine.
 /// This test reflects over Core.dll and fails the build if any forbidden assembly
-/// is referenced.
+/// is referenced. Both MonoGame/XNA (legacy) and Godot (M1+ port) are banned —
+/// keep both bans for the duration of the port so the in-flight branch can't
+/// regress either way.
 /// </summary>
 public sealed class CoreNoDependencyTests
 {
@@ -14,10 +16,12 @@ public sealed class CoreNoDependencyTests
     {
         "Microsoft.Xna",
         "MonoGame",
+        "Godot",
+        "GodotSharp",
     };
 
     [Fact]
-    public void Core_DoesNotReference_MonoGame()
+    public void Core_DoesNotReference_RenderingEngines()
     {
         var coreAssembly = typeof(Theriapolis.Core.C).Assembly;
         var referenced = coreAssembly.GetReferencedAssemblies();
@@ -28,7 +32,8 @@ public sealed class CoreNoDependencyTests
             .ToList();
 
         Assert.True(violations.Count == 0,
-            $"Theriapolis.Core must not reference MonoGame/XNA. Violations: {string.Join(", ", violations)}");
+            $"Theriapolis.Core must not reference any rendering engine (MonoGame/XNA/Godot). " +
+            $"Violations: {string.Join(", ", violations)}");
     }
 
     /// <summary>
diff --git a/Theriapolis.Tools/Commands/WorldgenHash.cs b/Theriapolis.Tools/Commands/WorldgenHash.cs
new file mode 100644
index 0000000..3e5af1a
--- /dev/null
+++ b/Theriapolis.Tools/Commands/WorldgenHash.cs
@@ -0,0 +1,81 @@
+using Theriapolis.Core.World.Generation;
+
+namespace Theriapolis.Tools.Commands;
+
+/// <summary>
+/// worldgen-hash --seed &lt;n&gt; [--data-dir &lt;dir&gt;]
+///
+/// Runs the full worldgen pipeline and prints the FNV-1a hashes of every
+/// output channel (elevation, moisture, temperature, biomes, settlements,
+/// polylines) plus the per-stage hash dictionary. Used as a determinism
+/// oracle for the Godot port — the Godot host prints the same hashes,
+/// they must match byte-for-byte.
+/// </summary>
+public static class WorldgenHash
+{
+    public static int Run(string[] args)
+    {
+        ulong seed = 12345;
+        string dataDir = ResolveDataDir();
+
+        for (int i = 0; i < args.Length; i++)
+        {
+            switch (args[i].ToLowerInvariant())
+            {
+                case "--seed":
+                    if (i + 1 < args.Length)
+                    {
+                        string raw = args[++i];
+                        seed = raw.StartsWith("0x", StringComparison.OrdinalIgnoreCase)
+                            ? Convert.ToUInt64(raw[2..], 16)
+                            : ulong.Parse(raw);
+                    }
+                    break;
+                case "--data-dir":
+                    if (i + 1 < args.Length) dataDir = args[++i];
+                    break;
+            }
+        }
+
+        if (!Directory.Exists(dataDir))
+        {
+            Console.Error.WriteLine($"Data directory not found: {dataDir}");
+            return 1;
+        }
+
+        Console.WriteLine($"[worldgen-hash] seed=0x{seed:X} data-dir={dataDir}");
+        var ctx = new WorldGenContext(seed, dataDir);
+        WorldGenerator.RunAll(ctx);
+        var w = ctx.World;
+
+        Console.WriteLine($"[worldgen-hash] === FNV hashes ===");
+        Console.WriteLine($"[worldgen-hash] elevation     = 0x{w.HashElevation():X16}");
+        Console.WriteLine($"[worldgen-hash] moisture      = 0x{w.HashMoisture():X16}");
+        Console.WriteLine($"[worldgen-hash] temperature   = 0x{w.HashTemperature():X16}");
+        Console.WriteLine($"[worldgen-hash] biomes        = 0x{w.HashBiomes():X16}");
+        Console.WriteLine($"[worldgen-hash] settlements   = 0x{w.HashSettlements():X16}");
+        Console.WriteLine($"[worldgen-hash] polylines     = 0x{w.HashPolylines():X16}");
+        Console.WriteLine($"[worldgen-hash] === Per-stage hashes ({w.StageHashes.Count}) ===");
+        foreach (var kv in w.StageHashes.OrderBy(k => k.Key, StringComparer.Ordinal))
+            Console.WriteLine($"[worldgen-hash] {kv.Key,-32} = 0x{kv.Value:X16}");
+        return 0;
+    }
+
+    private static string ResolveDataDir()
+    {
+        string local = Path.Combine(AppContext.BaseDirectory, "Data");
+        if (Directory.Exists(local)) return local;
+
+        string? dir = AppContext.BaseDirectory.TrimEnd(
+            Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar);
+        for (int i = 0; i < 6; i++)
+        {
+            if (dir is null) break;
+            string candidate = Path.Combine(dir, "Content", "Data");
+            if (Directory.Exists(candidate)) return candidate;
+            dir = Path.GetDirectoryName(dir);
+        }
+
+        return local;
+    }
+}
diff --git a/Theriapolis.Tools/Program.cs b/Theriapolis.Tools/Program.cs
index 4708110..3c67d99 100644
--- a/Theriapolis.Tools/Program.cs
+++ b/Theriapolis.Tools/Program.cs
@@ -10,6 +10,7 @@ return args[0].ToLowerInvariant() switch
 {
     "hello"              => Hello(),
     "worldgen-dump"      => WorldgenDump.Run(args[1..]),
+    "worldgen-hash"      => WorldgenHash.Run(args[1..]),
     "settlement-report"  => SettlementReport.Run(args[1..]),
     "tile-inspect"       => TileInspect.Run(args[1..]),
     "tactical-dump"      => TacticalDump.Run(args[1..]),
@@ -49,6 +50,10 @@ static void PrintHelp()
     Console.WriteLine("                --out <file.png>");
     Console.WriteLine("                [--data-dir <dir>]");
     Console.WriteLine("                [--show-violations]");
+    Console.WriteLine("  worldgen-hash --seed <n>          Run full pipeline and print FNV-1a hashes (elevation,");
+    Console.WriteLine("                [--data-dir <dir>]  moisture, temperature, biomes, settlements, polylines)");
+    Console.WriteLine("                                    plus per-stage hashes. Determinism oracle for the");
+    Console.WriteLine("                                    Godot port (compare to Godot host's smoke-test output).");
     Console.WriteLine("  settlement-report --seed <n>      Run full pipeline and print settlement report.");
     Console.WriteLine("                [--data-dir <dir>]");
     Console.WriteLine("  tile-inspect --seed <n>           Print polylines/bridges near a reported tile.");