Multiplayer first person shooter games with 2-player online support

F.E.A.R. 3

Players: 4 local, 0 online

Call of Duty: Black Ops

Players: 6 local, 360 online

Titanfall 2

Players: 4 local, 0 online

Serious Sam HD: The First Encounter

Players: 4 local, 360 online

Call of Duty: Black Ops 3

Players: 4 local, 0 online

Synergy (HL2 mod)

Players: 16 local, 0 online

Starship Troopers

Players: 8 local, 0 online

Tom Clancy's Rainbow Six Vegas

Players: 4 local, 0 online

Team Fortress 2

Players: 6 local, 0 online

Aliens vs Predator

Players: 4 local, 360 online

Call of Duty: World at War

Players: 4 local, 0 online

Far Cry 5

Players: 2 local, 0 online

DOOM 3: Last Man Standing (Mod)

Players: 16 local, 0 online

Call of Duty: Black Ops 3

Players: 4 local, 0 online

Will Rock

Players: 2 local, 0 online

Duke Nukem 3D

Players: 8 local, 360 online

Judge Dredd: Dredd vs. Death

Players: 2 local, 0 online

Mission Against Terror

Players: 8 local, 0 online

AirBuccaneers

Players: 16 local, 0 online

Interstellar Marines

Players: 4 local, 0 online

Space Hulk: Deathwing

Players: 4 local, 0 online

Duke Nukem 3D: 20th Anniversary Edition World Tour

Players: 8 local, 0 online

Fallout 76

Players: 4 local, 0 online

Serious Sam Collection

Players: 16 local, 0 online

Hexen 2

Players: 8 local, 0 online