The dungeons do give some variations with some rooms containing puzzles and some enemies. But the enemies got out of the rooms real quick and didn't seem to be bound to it. A border for them would fix that problem. The rewind ability which reverses the enemies moves is a bit unbalanced. If you spam "r" while chased by enemies you can keep them easily at distance and have enough time for shooting. A cooldown for the ability would make it more interesting to play against them. The tutorial you provided right at the beginning was pretty good and explained the game mechanics very quick and easy. Keep it up!