Adventures of Pip is a 2D side scrolling action platform video game

In Adventures of Pip, the player plays as Pip, a single pixel born into a world of hi-res and lo-res characters. As Pip defeats his enemies, he gains the ability to evolve into an 8-bit hero and later a 16-bit hero. Each evolution has its advantages and disadvantages. Pip must switch between his evolutions to complete levels. Players will need to evolve and devolve, wall jump, run, shove, break blocks, float, collect, and fight their way through bosses and henchmen till they get to the Evil Queen DeRezia.

https://en.wikipedia.org/wiki/Adventures_of_Pip