Wai Wai World 2 - SOS!! Parsley Jou

A man in a robot suit liberates worlds inspired by the wonderful Konami games of the 1980s. From the start of his journey, he has a double jump, and by holding one of the on-screen upgrades, you can temporarily transform into one of the heroes of the past by pressing up+jump. Helpers include noble thief Goemon, vampire fighter Simon Belmont, samurai Getsu Fuuma, baby Upa and soldier Bill (from Contra). The adventure is broken up by flying stages, two of which are easily recognisable as Gradius and TwinBee. There are also forks! The graphics are noticeably improved, and the characters are rendered in chibi style.