Nice concept to use the cycle of the day to switch roles which drastically changes the gameplay. The player can anticipate what's coming once they got used on the first cycle, with it, they can feel that the level's about to end and start anew, and the game executed it nicely. Also, the large sizes of the sun and moon helped on emphasizing what's about to come and the game's core mechanic itself.
The only issue I encountered is the camera as I can't see enough towards the direction I'm heading to in which the enemies are coming from.
It is a nice jam game, well done!