Claude Fable 5.1 costs 30% more than Fable 5 on a Blender-to-Godot racing build, with richer PBR worlds

Anthropic’s Claude Fable 5.1 and Claude Fable 5 finished the same one-shot racing-game prompt—model the car and environment in Blender with physically based rendering (PBR) materials, import into Godot, write driving physics, and ship a HUD—in roughly an hour, but Fable 5.1 spent about 30% more and returned far more detailed assets. In that unattended comparison, Fable 5.1 used 1.2 million tokens for $123.98 in 59.8 minutes; Fable 5 used 897,000 tokens for $95.87 in 57.3 minutes. Fable 5 produced a playable game with acceptable controls and HUD but basic meshes and stiff handling. Fable 5.1 delivered detailed PBR models and a track that felt more alive while driving.