Looks like fun game and have four players CO-OP
Description: (taken from developer site)
A hack and slash action adventure, set in a fantasy pixel art environment. Solo or cooperate in this adventure from bottom to top of Castle Hammerwatch. Kill hordes of enemies with varied looks and features through four unique enviroments with traps, hidden secrets and puzzles.
The game is inspired by the old Gauntlet-series, but adds a lot with online support, character development, complex levels, bosses, and much more. Like gauntlet, the focus is fast paced action, but with elements that forces you to think just a bit more!
Platforms: PC, MAC and Linux