Opus 5.5 builds 3D Terraria-style game in eight days

0xMarioNawfal @RoundtableSpaceOriginally posted 2026.10.07

Open original on X

Claude Opus 5.5 built a 3D version of a Terraria-style game in eight days, with the creator writing none of the code themselves. → The post says the game has 346,000 lines of C# running on a custom engine, not Unity or Godot → It claims 3,369 items and 313 enemies and bosses → The original creator and any code repository have not been publicly identified in the post → Terraria is owned by Re-Logic, and the project is not an official release