Like more than one of them
19 games close to two or more of Sizeable, 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
Crazy Machines 3
Garry's Mod, but a puzzle game, and a tenth of the hours
Loved · 95%Physics · SandboxAlso like Sizeable
Ravenfield
Garry's Mod, but single-player, and a third of the hours
Loved · 97%Sandbox · FPSAlso like Left 4 Dead 2
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
Totally Accurate Battlegrounds
Garry's Mod, but free to play, and a battle royale
Liked · 88%Physics · SandboxAlso like Left 4 Dead 2
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
Witch It
Sizeable, but a party game, and a stealth game
Liked · 89%Hidden Object · FantasyAlso like Left 4 Dead 2
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
Content Warning
Garry's Mod, but a horror game, and procedurally generated
Loved · 94%Physics · Online Co-OpAlso 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
How to Fish
Garry's Mod, but with fishing, and a tenth of the hours
Loved · 95%Physics · Online Co-OpAlso like Left 4 Dead 2
Zombie Panic! Source
Left 4 Dead 2, but half the hours, and more divisive
Liked · 85%Zombies · FPSAlso like Garry's Mod
Splitgate
Garry's Mod, but free to play, and an arena shooter
Loved · 91%FPS · PhysicsAlso like Left 4 Dead 2
Unturned
Left 4 Dead 2, but a survival crafting game
Loved · 91%Zombies · SurvivalAlso like Garry's Mod
More like Garry's Mod
11 games closest to Garry's Mod of your picks
Scrap Mechanic
Garry's Mod, but a survival crafting game, and with base building
Loved · 92%Building · Physics
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
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.