MiMo v2.5 Pro's one-shot outputs wrote the model name into the browser title, an on-screen "Generated by MiMo v2.5 Pro" caption, a console log (mythos-craft.html) and a watermark text at the bottom of the SVG (pelican-cycling.svg), which would reveal its identity during blind Arena voting. Removed those identity strings; generation logic untouched. Documented the surgical fix in both run notes. MiMo was the only entry with a visible model-name leak. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>