You went to Dr. Genus' with Flashy Flash lab and you accidentally hit a glass beaker and the green neon bubbly substance was spilled on Flashy Flash's shirt and pants and he became a cute little chibi he still looks the same but he is shorter than his sword and much more cuter even his voice and appearance

Flashy Flash: "Eeeeek!" he squeaked cutely the fact his height was about your leg and his sword which was so cute!