Garry's Mod

Garry's Mod, often abbreviated as GMOD, is a sandbox physics game using a modified Source engine, created by Garry Newman and his games studio, Facepunch Studios. It was originally a modification for Valve's Half-Life 2 on December 24, 2004, but was later made into a standalone game on Steam on November 26, 2009.

Prop Hunt
Prop Hunt is a Garry's Mod gamemode based on the popular kids game, Hide and Seek. The game consists of two teams of players, the Props and the Hunters. The Props team have 45 seconds to transform themselves into a prop and hide themselves by blending in with the environment. After those 45 seconds, the Hunters are unblinded and have 3–5 minutes to find and eliminate all members of the Props team.

Murder
Murder is a Garry's Mod gamemode in which a team of players are split into 4-7 vs 1 teams. The 4-7 team are the bystanders, who cannot do anything other than run on their own, however, one bystander will be provided with a revolver with infinite one-bullet clip (which can be taken by other bystanders if it is dropped) which must be used to kill the 1 person in the opposing team, the Murderer. The murderer looks like a normal bystander and must kill all of the bystanders (including the one with the gun) all the while, keeping their allegiance secret.

Trouble In Terrorist Town
Trouble in terrorist town is a Garry's Mod gamemode which is about a group of "terrorists" who have traitors among them, out to kill everyone who's not a traitor. There are several roles; Innocent's who must defend themselves from traitors. Detectives, whose roles is to uncover who the traitors are, and Traitors who must kill every other player who is not a Traitor in order to win. Rounds are around 5 minutes long and will only end when either, all innocents and detectives are dead, or all traitors are dead.

Sandbox
Sandbox is the default Garry's Mod gamemode where players are free to build and create anything using a variety of tools, such as a physgun. The gamemode has a menu with a variety of objects that can be spawned in and used.

Melon Bomber
Melon Bomber is a Garry's Mod gamemode similar to bomberman, but instead of bombs, it's melons, and instead of a 2D game, it's a Garry's Mod gamemode.

Deathrun
Deathrun is a Garry's Mod gamemode where the 'Runners' try to get to the end of a map, while the 'Deaths' activate traps to kill the Runners. It's all about timing, whether you're a Runner, or a Death!

In-Yogiverse
Garry's Mod was introduced through different sandbox Let's Build challenges with Lewis and Simon, starting with Spaceships, as well as a 2012 Christmas stream with Sips and Sjin. It later gained in popularity on Sips' channel, who began posting highlight reels of regular games with Turps and Hat Films. Lewis and Simon also began posting reels of team games with groups of other Yogs, such as Hat Films, Sips, Sjin, Hannah, and Martyn. Pyrion Flax hosted a livestream of Garry's Mod Prop Hunt that featured himself, Lewis, Rythian, Nilesy, Zoey, Zylus, Alex, Tee, Ravs, Daltos, Benji, and Danny. The most frequently played games include Prop Hunt, Trouble in Terrorist Town (TTT), and Murder.

Outside of GMod games, there are occasional highlight videos posted to Lewis and Simon's channel featuring multiple Yogs playing around with different dupes built in sandbox mode by other players. There are also team theme racing challenges, in which each team must build to a group and/or main theme and then race their build against each other, usually featuring teams such as Lewis and Duncan, Hat Films, and Sips and Sjin.