Very cool mechanics for a puzzle game! Puzzle design was also pretty decent. Definitely needs some polish, checkpoints were somewhat pointless once you reach the double character stage since it's easy to checkpoint an impossible state. Would definitely like to see this grow into a larger puzzle game :)
(By the way, not sure if you're a member of the Thinky Games discord yet, but it's a great place to discuss puzzle games and puzzle game development, highly recommended!)