[simply Nathan]

A mouse wrestling several weasels and winning. Weasel pile progressively adds more and larger weasels; once larger weasels than are extant in life start being called in as reinforcements, mouse starts growing to match the largest relevant weasel and only winning more efficiently.

Eventually, it becomes a kaiju battle between a giant weasel and a giant mouse (both anthropomorphic enough at this point to actually resemble men wearing costumes)