Chalvo 55 is a 2D side-scrolling puzzle platformer where the player controls a small robot tasked with exploring the levels of a spaceship hovering above Earth. The gameplay emphasizes solving puzzles and maneuvering around enemies and traps. The player character has the ability to curl into a bouncing ball to traverse past obstacles.
Chalvo was originally designed as the protagonist of a Virtual Boy-exclusive game, Bound High, which would have featured it bouncing through 2D levels from a top-down perspective. After it was cancelled due to the Virtual Boy's untimely death, Chalvo 55 was developed as a replacement using the same character and setting.