Very interesting concept, lots of fun to play, but mostly after 2-3 games to really grasp what you're supposed to do. Still, it seems to be quite a bit luck-based, as where the Overmind spawns determines how easy the game is. Nice level-design, more levels would make it less learnable, but this is a game jam so no critique there.
The music was fitting, but the sounds seemed to have been going off in a random order which made it funny sometimes. The pixel art and the overall design was nice and readable, except for the flames that were behind the knights. It was hard to determine whether there was still a flame on a knight or it was just their feathers.
Lastly I encountered a bug in the download version, where I couldn't move the units I placed in the first round. Even the enemies couldn't kill them so they just remained on-screen. A restart fixed this issue.
Overall great game, good to play something that isn't really skill-based, but stategic.