Same-Prompt Test Finds DeepSeek-V4.1-Flash About 90% Cheaper Than GPT-5.6 Sol and Claude Opus 5

GPT-5.6 Sol, DeepSeek-V4.1-Flash, and Claude Opus 5 were given the same one-shot design prompt, and the invoice is what split them. In a public Command Code /design showcase that asked each model to build a Subway Surfers-style endless runner as a single HTML Canvas file, DeepSeek-V4.1-Flash produced the kept file for $0.024, versus $0.3265 for OpenAI's GPT-5.6 Sol and about $0.37 for Anthropic's Claude Opus 5 — roughly a 90% cut against both flagships.