Doing timed group jeopardy style competition event
Some items have unlimited guesses some don't, without discussing with the group this dude tried to bruteforce everything out the gate and removed a range of easy to significant points that we could have earned by exhausting our guesses.
Same dude spent our limited points pool on hints without consulting. One was for a question our teammate was just wrapping up, another two he had no intentions on completing. Out of our group total of 667 points (second place overall) he contributed -97.
Same dude stacked his mf'n cup into mine (before I was done, without asking).