Single-player games like Garry's Mod
Below are 16 single-player Steam games similar to Garry's Mod, ranked by player overlap. Every pick carries Steam's Single-player category, so multiplayer-only titles or always-online games don't sneak in. imho.run pulls the category data from Steam directly — Single-player here matches what the store labels.
Want the full alternatives list (paid + free + Steam Deck + cheaper picks)? See the parent games like Garry's Mod page.
Ranked picks
- 1
Tabletop Simulator
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie and Simulation with Garry's Mod.
Tabletop Simulator is the only simulator where you can let your aggression out by flipping the table! There are no rules to follow: just you, a physics sandbox, and your friends. Make your own online board games or play the thousands of community created mods. Unlimited gaming possibilities!
- 2
Terraria
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie with Garry's Mod.
Dig, fight, explore, build! Nothing is impossible in this action-packed adventure game. Four Pack also available!
- 3
7 Days to Die
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie with Garry's Mod.
7 Days to Die is an open-world game that is a unique combination of first-person shooter, survival horror, tower defense, and role-playing games. Play the definitive zombie survival sandbox RPG that came first. Navezgane awaits!
- 4
Space Engineers
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie and Simulation with Garry's Mod.
Space Engineers is a sandbox engineering game where you design and build ships, stations, and planetary bases in a fully destructible environment. Explore planets and space, mine resources, survive hazards, and engage in combat alone or with friends in Creative or Survival modes.
- 5
Kerbal Space Program
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie and Simulation with Garry's Mod.
In Kerbal Space Program, take charge of the space program for the alien race known as the Kerbals. You have access to an array of parts to assemble fully-functional spacecraft that flies (or doesn’t) based on realistic aerodynamic and orbital physics.
- 6
Scrap Mechanic
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie and Simulation with Garry's Mod.
Enter the creative paradise of Scrap Mechanic! Build fantastic machines, go on adventures with your friends and defend against waves of evil Farmbots in this imaginative multiplayer survival sandbox. With Scrap Mechanic’s powerful creation tools you can engineer your own adventures!
- 7
Teardown
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie and Simulation with Garry's Mod.
Prepare the perfect heist in a fully destructible, simulated voxel world. Tear down walls with vehicles or use explosives to create your own shortcuts. Shape the environment to your advantage in the most creative ways you can imagine. Play solo or with up to 12 players in multiplayer.
- 8
People Playground
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Casual and Indie with Garry's Mod.
Shoot, stab, burn, poison, tear, vaporise, or crush ragdolls in a large open space.
- 9
Half-Life 2
Single-player alternative to Garry's Mod — playable solo, no multiplayer required.
Reawakened from stasis in the occupied metropolis of City 17, Gordon Freeman is joined by Alyx Vance as he leads a desperate human resistance. Experience the landmark first-person shooter packed with immersive world-building, boundary-pushing physics, and exhilarating combat.
- 10
Portal
Single-player alternative to Garry's Mod — playable solo, no multiplayer required.
Portal™ is a new single player game from Valve. Set in the mysterious Aperture Science Laboratories, Portal has been called one of the most innovative new games on the horizon and will offer gamers hours of unique gameplay.
- 11
Portal 2
Single-player alternative to Garry's Mod — playable solo, no multiplayer required.
The "Perpetual Testing Initiative" has been expanded to allow you to design co-op puzzles for you and your friends!
- 12
Zeno Clash
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie with Garry's Mod.
Zeno Clash is an action/fighting game set in a punk fantasy world. The game is played from a first person perspective and the combat is generally up close and brutal. Experience a deep storyline set in a fantastic world.
- 13
s&box
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie with Garry's Mod.
Our spiritual successor to Garry's Mod, this is a game creation platform built on the Source 2 engine. Play, create, and share games, explore community creations, and experience endless sandbox fun with powerful modern tools.
- 14
Chippy
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie with Garry's Mod.
Chip destructible bosses apart pixel-by-pixel in this twin-stick bullet-hell shooter.
- 15
Clatter
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie with Garry's Mod.
Create and command your own customizable squads of fighting robots in this turn-based, arena tactics game.
- 16
Chunks
Single-player alternative to Garry's Mod — playable solo, no multiplayer required. Shares Indie and Simulation with Garry's Mod.
Build and share worlds, design rideable roller-coasters, or try out user created game modes and tools in this block-based VR sandbox.