Garry's Mod, sandbox game, physics-based, user-generated content, multiplayer, single-player, creative freedom, modding community, Steam Workshop, Half-Life 2 assets, face poser tool, ragdoll posing, contraption building, interactive environments, comedy, no predefined objectives, PC game, Source engine, age rating varies by country, ESRB Teen, PEGI 12, cartoon violence, mild language, online interactions.