Changelog:
- Added split-screen co-op for up to 2 players
- Reworked heavy weapons to be power-ups (can still be bought as store items using a difficulty modifier)
- Split rocket launcher into two different heavy weapons: RPG and Fireworks Launcher. Neither will have an upgrade anymore
- Buffed all heavy weapons
- Removed invulnerability for clown zombie when dodging attacks and increased their dodge speed