It was not error for the trial court to have failed to instruct the jury that it was a partial defense to mayhem that appellant acted under a genuine but unreasonable belief that he needed to defend himself. Imperfect self defense has no application to a charge of mayhem. Mayhem only requires the intent to vex, injure, or annoy. A belief that one is acting self-defense, whether unreasonable or reasonable, does not negate the element of malice. Therefore, failure to instruct on that rule reflects neither error nor ineffective assistance of counsel for failing to request the instruction.