used in a threatening context, to warn a person who is being increasingly annoying that they are about to get smacked/punched/kicked in the face/stomach/groin unless they refrain from annoying you further

To pull a "karp," is to do something completely unexpected and lucky in order to gain an advantage during an athletic event.

also referred to as "pulling something out of your ass."

The term was named after a Los Angeles wrestler, Karp, who would always win his matches through half-assed made-up moves at the last second. The term was subsequently spread by his team.