At its core:
Trouble in Terrorist Town (TTT) is a gamemode for (and included in) Garry's Mod. It's about a group of Terrorists who have traitors among them, out to kill everyone who is not a traitor.
A small number of players (typically 25%) is selected as Traitors, who have to kill all the Innocent players (ie. the rest). Those innocents know there are people out to get them, and they're in the majority, but they do not know who the traitors are.
The Traitors must use the element of surprise and their special equipment if they are to succeed. The Innocent just have to survive, which means finding out who the Traitors are and killing them before they kill you. Of course everyone is holding a big gun, and everyone looks suspicious...
For the Innocent, knowledge is power: who is acting strangely? Who can be linked to evidence found on corpses? Who is still alive, even?
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