Like more than one of them
20 games close to two or more of Fort Solis, Garry's Mod and Left 4 Dead 2
SCP: Secret Laboratory
Left 4 Dead 2, but free to play
Loved · 91%FPS · Survival HorrorAlso like Garry's Mod
No More Room in Hell
Left 4 Dead 2, but free to play, and half the hours
Loved · 90%Zombies · SurvivalAlso like Garry's Mod
DOOM 3: BFG Edition
Fort Solis, but a first-person shooter, and a survival horror game
Liked · 86%Mars · SpaceAlso like Left 4 Dead 2
PlanetSide 2
Garry's Mod, but free to play, and an MMO
Liked · 80%FPS · ShooterAlso like Left 4 Dead 2
Call of Duty: Black Ops II
Left 4 Dead 2, but a quarter of the hours, and more divisive
Liked · 86%FPS · Team-BasedAlso like Garry's Mod
Ravenfield
Garry's Mod, but single-player, and a third of the hours
Loved · 97%Sandbox · FPSAlso like Left 4 Dead 2
Counter-Strike Nexon
Left 4 Dead 2, but free to play, and PvP
Mixed · 67%Zombies · FPSAlso like Garry's Mod
Call of Duty: Modern Warfare 2 (2009)
Garry's Mod, but military, and a fifth of the hours
Loved · 93%FPS · ShooterAlso like Left 4 Dead 2
Red Faction: Guerrilla Steam Edition
Fort Solis, but a third-person shooter, and open world
Loved · 90%Mars · Sci-fiAlso like Garry's Mod
Zombie Panic! Source
Left 4 Dead 2, but half the hours, and more divisive
Liked · 85%Zombies · FPSAlso like Garry's Mod
R.E.P.O.
Garry's Mod, but a survival horror game, and a quarter of the hours
Loved · 96%Physics · ComedyAlso like Left 4 Dead 2
Unturned
Left 4 Dead 2, but a survival crafting game
Loved · 91%Zombies · SurvivalAlso like Garry's Mod
STAR WARS Battlefront II
Garry's Mod, but a third-person shooter, and a quarter of the hours
Liked · 88%FPS · ShooterAlso like Left 4 Dead 2
Interstellar Marines
Left 4 Dead 2, but sci-fi, and a tenth of the hours
Divisive · 53%FPS · Co-opAlso like Fort Solis and Garry's Mod
More like Fort Solis
3 games closest to Fort Solis of your picks
Metal Garden
Fort Solis, but a first-person shooter, and half the hours
Loved · 97%Immersive · Narrative
Mouthwashing
Fort Solis, but a psychological horror game, and even better loved
Loved · 95%Walking Simulator · Narrative
More like Garry's Mod
6 games closest to Garry's Mod of your picks
Space Engineers
Garry's Mod, but a survival crafting game, and with base building
Liked · 89%Building · Sandbox
Fireworks Mania - An Explosive Simulator
Garry's Mod, but a hobby sim, and a tenth of the hours
Loved · 97%Sandbox · Physics
Hot Dogs, Horseshoes & Hand Grenades
Garry's Mod, but in VR, and half the hours
Loved · 97%Physics · Sandbox
More like Left 4 Dead 2
1 games closest to Left 4 Dead 2 of your picks
STAR WARS Republic Commando
Left 4 Dead 2, but in space, and a third of the hours
Loved · 96%FPS · Shooter
How this list is made
Each game is measured against each of your picks the way a games-like list measures it: the Steam community tags, Steam genres and IGDB themes they share, each counting for more the fewer games carry it. A game's place is how alike it is to your picks together, as a share of each pick's best match, so one alike to two of them comes before one alike to just one. It must be close to at least one of them, as close as it would have to be on that game's own list.
None of your picks is on the list, nor a second release of one, nor a game of their own series. Up to 30 games are shown. Under each name, the kinds it shares with the pick it is closest to, and how it differs from that pick.