Block 21 is a puzzle game where players control a block as it moves along a winding path. The goal is to navigate the block through obstacles and reach the end of the track.
The player must rotate sections of the track to create a path for the block to follow. The twist is that the block can only traverse the track in a specific direction, requiring the player to think ahead and plan their moves carefully. The game runs in the browser with no download or registration required, allowing players to jump in and start playing immediately.