I love the idea of the rewind powerup causing the graphics to revert to a more primitive style!! This is a very nice game with some smooth use of the players interaction with the mounted gun. I think slowing the enemies down a bit will give the player the ability to last for longer and therefore play more of the game, as right now there is not a lot of time between the enemy appearing on screen and damaging your base. I think you have used the theme very creatively and hope you enjoyed making this fun game! Play my game if you have a moment, I would love to have some feedback from another participant in this jam!