Team Fortress 2
Firstly, we have the legendary Team Roomba using a glitch to build sentry guns under the ground. And healing enemy spies. Andusing customsprays and well-placed teleports to give their own team a face full of filth.And then teleporting half their team behind an inescapable fence. And more.
Loving your work gents, loving your work.
Roomba again, this timeputting teleport exits right in front of sentry guns, the cheeky scamps. And then they use a door glitch to lock their entire team in the start room, before ransoming off their freedom in a geography quiz. The other players make this far funnier than it has any right to be. Especially the northern English guy about halfway through.
And finally, how would you react if after being fragged senseless over a long hard battle, seemingly without a single medic on the server, you eventually found them all and they were just having a bit of a party without you?