Nice idea for a game! Not too much feedback that hasn't already been stated, the earlier levels were more fun but I found the last level very challenging. I did manage to beat it but it felt largely luck based. I hard a hard time understanding how the enemies would move, it seemed that they would move the direction you moved, but only sometimes. I guess that is what makes a challenging opponent!
My main point of feedback would be making sure you have the game's scaling nailed down, the window was very large but the game board was very small for me, so it was hard to see what was going on.
All that being said, great job getting the game together, hope to see you in the next jam!