Very nice game, I really liked the shooting and pulling mechanic. It's really fun when the hordes get insanely huge. It's kind of a relief knowing that death is inevitable, it allows players to relax while they're alive :P
I've read down there that this is your first game, congratulations for that, you have a brilliant future if you keep going at this.
A tip for your next jam is to avoid creating a installer for your game, it's slower than unzipping and much slower than playing on the web, and most people rating games on game jams prioritize games that are faster to start.