Originating from trying to beat a high score in Tetris, tetblood is a noun meaning to one-up someone else or get revenge on someone whether in Tetris or in any aspect of life.
Rob is out for tetblood now that Jesse has the new high score.

"Dude, I think that guy is talking to your girl. If I were you, I would be out for tetblood on him."

This guy isn't just out for blood tonight on the football field, he is out for tetblood. Watch out.
by Clorn Puck Sart November 1, 2010
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