diff --git a/api/games/game-auth.ts b/api/games/game-auth.ts
new file mode 100644
index 00000000..46e2b5b3
--- /dev/null
+++ b/api/games/game-auth.ts
@@ -0,0 +1,123 @@
+import type { VercelRequest, VercelResponse } from "@vercel/node";
+import { createClient } from "@supabase/supabase-js";
+
+const supabase = createClient(
+  process.env.SUPABASE_URL || "",
+  process.env.SUPABASE_SERVICE_ROLE || "",
+);
+
+export interface GameAuthRequest {
+  game: "unity" | "unreal" | "godot" | string;
+  player_id: string;
+  player_name: string;
+  auth_token?: string; // Optional existing AeThex auth token
+  device_id?: string;
+  platform?: string; // "PC", "Mobile", "Console", etc.
+}
+
+export default async function handler(req: VercelRequest, res: VercelResponse) {
+  // Allow both GET (for testing) and POST (for actual auth)
+  if (req.method !== "POST" && req.method !== "GET") {
+    res.setHeader("Allow", "POST, GET");
+    return res.status(405).json({ error: "Method not allowed" });
+  }
+
+  try {
+    const { game, player_id, player_name, auth_token, device_id, platform } =
+      req.method === "POST" ? req.body : req.query;
+
+    if (!game || !player_id || !player_name) {
+      return res.status(400).json({
+        error: "Missing required fields: game, player_id, player_name",
+      });
+    }
+
+    const validGames = ["unity", "unreal", "godot", "roblox", "custom"];
+    if (!validGames.includes(String(game))) {
+      return res.status(400).json({
+        error: `Invalid game. Must be one of: ${validGames.join(", ")}`,
+      });
+    }
+
+    const gameType = String(game).toLowerCase();
+
+    // Find or create user for this game
+    const lookupKey = `${gameType}_player_id`;
+    let { data: userData } = await supabase
+      .from("user_profiles")
+      .select("id, auth_id, email, username")
+      .eq(lookupKey, String(player_id))
+      .single();
+
+    if (!userData) {
+      // Create new game player user
+      const email = `${String(player_id)}@${gameType}.aethex.dev`;
+      const username = `${gameType}_${String(player_id).substring(0, 8)}`;
+
+      const { data: newUser, error: createError } = await supabase
+        .from("user_profiles")
+        .insert({
+          [lookupKey]: String(player_id),
+          username,
+          user_type: "game_developer",
+          full_name: String(player_name),
+          email,
+          metadata: {
+            game: gameType,
+            player_id: String(player_id),
+            player_name: String(player_name),
+            platform: platform || null,
+          },
+        })
+        .select()
+        .single();
+
+      if (createError) {
+        console.error(`Failed to create ${gameType} user:`, createError);
+        return res.status(500).json({ error: "Failed to create user" });
+      }
+
+      userData = newUser;
+    }
+
+    // Generate game session token
+    const sessionToken = require("crypto").randomBytes(32).toString("hex");
+    const expiresAt = new Date(Date.now() + 7 * 24 * 60 * 60 * 1000); // 7 days
+
+    // Store game session
+    const { error: sessionError } = await supabase
+      .from("game_sessions")
+      .insert({
+        user_id: userData.id,
+        game: gameType,
+        session_token: sessionToken,
+        device_id,
+        platform,
+        expires_at: expiresAt.toISOString(),
+        last_activity: new Date().toISOString(),
+      });
+
+    if (sessionError) {
+      console.error("Failed to create game session:", sessionError);
+      return res.status(500).json({ error: "Failed to create session" });
+    }
+
+    // Return auth data for game
+    return res.status(200).json({
+      success: true,
+      session_token: sessionToken,
+      user_id: userData.id,
+      username: userData.username,
+      email: userData.email,
+      game: gameType,
+      expires_in: 604800, // 7 days in seconds
+      api_base_url: process.env.VITE_API_BASE || "https://aethex.dev/api",
+      docs_url: "https://docs.aethex.dev/game-integration",
+    });
+  } catch (error: any) {
+    console.error("Game authentication error:", error);
+    return res.status(500).json({
+      error: error?.message || "Authentication failed",
+    });
+  }
+}