Multiplayer shoot em up games for PC/Windows with 4-player online support
Mercenary Kings
Players: 4 local, 4 online
Chicken Invaders: Ultimate Omelette
Players: 0 local, 4 online
Shoot Many Robots
Players: 0 local, 4 online
XenoRaptor
Players: 4 local, 8 online
Rogue Continuum
Players: 4 local, 4 online
Zombie Party
Players: 4 local, 4 online
RiftStar Raiders
Players: 0 local, 4 online
Toon Shooters 2: The Freelancers
Players: 0 local, 5 online
sunny-place-2
Players: 0 local, 8 online
Rogue Robots
Players: 4 local, 4 online
Chicken Invaders: Revenge of the Yolk
Players: 2 local, 4 online
Chicken Invaders: Cluck of the Dark Side
Players: 2 local, 4 online
Chicken Invaders Universe
Players: 0 local, 99 online
Astrosmash
Players: 4 local, 4 online