Like more than one of them
23 games close to two or more of Garry's Mod, Euro Truck Simulator 2 and 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
Drive Beyond Horizons
Euro Truck Simulator 2, but a survival game, and a third of the hours
Mixed · 78%Driving · Automobile SimAlso like Left 4 Dead 2 and Garry's Mod
SCP: Secret Laboratory
Left 4 Dead 2, but free to play
Loved · 91%FPS · Survival HorrorAlso 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
BeamNG.drive
Euro Truck Simulator 2, but physics-driven, and with destruction
Loved · 97%Driving · Automobile SimAlso like Garry's Mod
Unturned
Left 4 Dead 2, but free to play, and a survival crafting game
Loved · 91%Zombies · SurvivalAlso like Garry's Mod
Counter-Strike Nexon
Left 4 Dead 2, but PvP, and more divisive
Mixed · 67%Zombies · FPSAlso like Garry's Mod
Railroads Online
Euro Truck Simulator 2, but co-op, and more divisive
Mixed · 75%Automobile Sim · DrivingAlso like Garry's Mod
Construction Simulator
Euro Truck Simulator 2, but co-op, and a third of the hours
Liked · 80%Transportation · DrivingAlso like Garry's Mod
My Summer Car
Euro Truck Simulator 2, but a survival game, and first-person
Loved · 95%Automobile Sim · DrivingAlso like Garry's Mod
Far Cry 4
Garry's Mod, but open world, and half the hours
Liked · 85%FPS · SandboxAlso like Left 4 Dead 2
RoadCraft
Euro Truck Simulator 2, but not open world, and half the hours
Mixed · 75%Driving · TransportationAlso like Garry's Mod
Blockland
Garry's Mod, but a quarter of the hours, and more divisive
Mixed · 74%Building · SandboxAlso like Left 4 Dead 2
Avatar: Frontiers of Pandora
Garry's Mod, but story-rich, and a third of the hours
Mixed · 78%Online Co-Op · ShooterAlso like Left 4 Dead 2
Sons Of The Forest
Garry's Mod, but a survival horror game, and with crafting
Liked · 88%Building · SandboxAlso like Left 4 Dead 2
7 Days to Die
Garry's Mod, but a base builder, and about survival
Liked · 87%Building · SandboxAlso like Left 4 Dead 2
Bodycam
Garry's Mod, but horror, and a tenth of the hours
Liked · 81%FPS · PhysicsAlso like Left 4 Dead 2
More like Garry's Mod
7 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
Just Cause 2
Garry's Mod, but a third-person shooter, and a quarter of the hours
Loved · 91%Sandbox · Physics
Hot Dogs, Horseshoes & Hand Grenades
Garry's Mod, but in VR, and single-player
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.