Ultimate Muscle: Legends vs. New Generation (2003) for GameCube was based on the anime Kinnikuman Nisei, blending wrestling mechanics with over-the-top superhero moves. Developed by AKI, it used a streamlined version of the No Mercy engine, making it mechanically sound and fun to play.

The roster included classic and new Kinnikuman characters, each with wild finishers and colorful arenas. Gameplay emphasized light/strong grapples, reversals, and dramatic special moves, striking a balance between sim depth and arcade flair. It received praise for accessibility and charm, remembered fondly as one of the best anime-to-wrestling adaptations.