O.S.B.T
O. S. B. T is when you're so bad at the game, one bullet finishes you. People in the xd clan use it to tease the weakest players.
"He got sniped and screamed like a girl. He’s O. S. B. T."
"I’m O. S. B. T. I couldn’t even survive one bullet."
"He got one shot and he’s O. S. B. T. That’s a disgrace."