Throughout Cat Bird's quest, he is swept through a total of four different planets. Each one is unique in theme, and most introduce some new mechanic that's used to create challenging levels. The planets all resemble cat heads, with pointy ears and feline features.
The four planets are:
Finishing the first three worlds ends the game; Zipsa, the fourth world, is DLC content, and completion of which is not necessary to reach the end of Cat Bird's journey.