Recent reviews by Inkwell The Dynamic

Garry's Mod is a physics sandbox that allows for experimentation, social interactions, and the absolute labyrinth of mods that is the Garry's Mod Workshop.

Really! I have played this game for 587.5 hours as of writing this, and about 4 or 5 hours of it were the vanilla game. In truth, practically all of it was sandbox with that vast majority including other people on a 4 person server. I could never find a Trouble in Terrorist Town server with enough people, and don't have enough people to play the game mode with on a private game, so that was off the list.

In summary, this game can be hard to put down until 100 hours, afterward it gets a bit bland (assuming you play on sandbox for the whole time and in the same simpleton fashion I did). This however is pretty easily remedied with gamemodes, maps, and other modded content that is so easy to access thanks to an in-game mod manager.

Perfect for killing time. 9/10