Multiplayer twin stick shooter games for PC/Windows with 4-player online support

Gatekeeper

Players: 0 local, 4 online

SYNTHETIK 2

Players: 0 local, 4 online

Alien Swarm: Reactive Drop

Players: 0 local, 8 online

It Came from Space, and Ate Our Brains

Players: 0 local, 4 online

HELLDIVERS

Players: 4 local, 4 online

Final Days

Players: 4 local, 16 online

Ultimate Zombie Defense

Players: 0 local, 4 online

Renegade Ops

Players: 2 local, 4 online

Ring Runner

Players: 2 local, 8 online

Alien Swarm

Players: 0 local, 4 online

Steel Storm: Burning Retribution

Players: 0 local, 8 online

Nature's Zombie Apocalypse

Players: 8 local, 8 online

From Space

Players: 0 local, 4 online

Madballs in...Babo: Invasion

Players: 0 local, 4 online

Nation Red

Players: 4 local, 4 online

Bunch of Heroes

Players: 0 local, 4 online

Hoard

Players: 0 local, 4 online

ProtoGalaxy

Players: 4 local, 4 online

Dual Core

Players: 4 local, 4 online

SCALPERS: Turtle and the Moonshine Gang

Players: 4 local, 4 online

NoReload Heroes

Players: 4 local, 4 online

Dead Sky

Players: 0 local, 4 online

Gunnheim

Players: 4 local, 4 online

Guardians of Orion

Players: 0 local, 4 online

Zombie Estate 2

Players: 4 local, 4 online