How Garry’s Mod Paved the Way for Modern Multiplayer Games

When Garry’s Mod (named for its original creator, Garry Newman) was released in 2004, it was originally just a mod for Half-Life 2 made within Valve’s Source game engine. It was a simple sandbox that let players spawn in and mess around with various props and characters from the game’s files. Valve would later publish a stand-alone release of the game — meaning that Garry’s Mod had gone from a mod of a Valve game to a game published by Valve, and the game developed mods of its own. Mods such as Morbus, Prop Hunt, and Trouble in Terrorist Town introduced many players to now-familiar genres like asymmetrical multiplayer and social deduction. Today, standalone games in those genres like Among Us and Prop Hunt are huge successes, but it isn’t a stretch to say they might not have existed at all had it not been for Garry’s Mod.

Trouble at the Old Mill

One of the most popular mods for Garry’s Mod is Trouble in Terrorist Town. The mod first appeared online back in 2009 and takes place in a satirical version of the game Counter-Strike, in which there are traitors among a group of terrorists. It’s up to the terrorists to discover just who the traitors are and kill them — meanwhile, the traitors must kill the rest of the terrorists without drawing too much attention to themselves to win.

Each player is assigned a different role: traitor, innocent, or detective. Detectives attempt to determine the identity of the traitors, while innocents simply have to survive until the end of the round. The game’s premise isn’t entirely original — it’s based on Dimitry Maximoff’s party game Mafia (also known as Werewolf) in which players use deduction to determine the identities of the killers before it’s too late — and TTT wasn’t even the first game of its kind available on Steam. The Ship was released three years earlier and features a similar premise, with players trying to stealthily kill each other off. It was even made in the Source engine, just like Garry’s Mod. So if TTT wasn’t an original concept, why did it become so popular and go on to inspire so many other titles? Partly, it was a case of being in the right place at the right time.

In the early 2010s, the Let’s Play format was immensely popular on YouTube. This was due in part to the emergence of Multi-Channel Networks like Machinima and Full Screen that managed (and often mis-managed) multiple creators at a time. Toby Turner was still one of the most popular channels for gaming, PewDiePie hadn’t yet fallen from grace, Smosh Games had just been created, and Rooster Teeth’s Let’s Play channel was just starting to take off. Twitch had also been around for about a year, and at the time was more strictly focused on video games than it eventually came to be.

heseSome of t Let’s Players and streamers started to make videos about TTT since they had already seen success from Garry’s Mod videos. This brought more eyes to the mod than ever before. Bad King Urgrain, the mod’s creator, noticed this at the time, saying the mod “was starting to get a bump in traffic out of the blue.” For instance, one of the most popular Garry’s Mod Let’s Players at one point was Seananners — all of his videos on the mod have over 1 million views. His first — uploaded in August 2021 — has 3.3 million.

TTT may not have invented the social deduction genre, but it certainly paved the way for the games that followed it. Among Us is one of them. In Among Us, players attempt to complete various tasks on a space station while trying to determine the identities of the imposters. Just like TTT, Among Us was originally enjoyed by a small, but passionate community until streamers and YouTubers picked it up in 2020, bringing it to new audiences. In that year, Among Us was played by prominent twitch streamers and politicians, Tik Toks about the game reached 13 billion views, and it was featured during the Twitch Rivals tournament, which pits prominent streamers against one another in competitive games.


One of These Things is Not Like the Other…

But this wasn’t the first time a mod from Garry’s Mod inspired a game — that accolade belongs to Prop Hunt. In this mod, one team of players is disguised as inanimate objects while the other team tries to find them. It was originally made for Counter-Strike: Source before making its way to Garry’s Mod in 2012, and just like TTT, it experienced a boost in popularity thanks to videos from Youtubers like Seananners.

Several games have been directly inspired by Prop Hunt, with the format showing up as a mod for many other titles as well. Midnight Ghost Hunt and Propnight are PC games that combine prop hunt gameplay with survival horror flavor. For console players, there’s Call of Duty — each COD game since 2017 has featured a version of the game. The latest game, Vanguard, has even hinted at the mode making a return.

Another popular mod for Garry’s Mod that has influenced multiplayer gaming is Morbus. The mod debuted in 2012, and like Prop Hunt and TTT, it  gained a following thanks to streamers and Let’s Players. Morbus is an asymmetrical multiplayer game with a simple premise: there is one alien amongst a group of humans, and it’s up to the humans to discover and kill the alien before it kills them. This is very similar to TTT — the main difference being that the alien can turn other human players into aliens.

Since the release of Morbus, there’s been an explosion of horror-themed asymmetrical multiplayer games  — Friday the 13th, Last Year, and White Noise 2, to name a few. The most popular of these games is Dead by Daylight, which has been supported since its release in 2016 and has featured horror movie slashers like Scream’s Ghostface and Texas Chainsaw Massacre’s Leatherface as DLC. The Texas Chainsaw Massacre will also be receiving an asymmetrical multiplayer game at some point.

Garry’s Mod shows that when given the right tools, amateur developers can create projects that go on to fuel huge new trends in game design. TTT, Morbus, and Prop Hunt were all created by communities of passionate gamers who wanted to make something different, and that passion rubbed off on the people who played these mods, or at least watched them on Youtube. We are already starting to witness these games inspired by mods go on to inspire other games, as, for instance, a number of social deduction games set in space have popped up on Steam thanks to the popularity of Among Us. It’s funny to think that some of the biggest surprise hits of the last few years might never have come into being were it not for a little mod that could.