"We don't know what made them so crazy, but the black-and-white one seems to be their leader."
―Sera Jossi[src]

Wrhisch was a male Wookiee who at some point had gone insane and went berserker. Somehow, he caused other Wookiees in the vicinity of Kachirho to go berserk as well, and the berserkers began to interfere with the business of Sera Jossi. She began posting bounties on the Wookiees, and eventually a spacer managed to defeat Wrhisch. He never bothered to learn what made the Wookiee go insane and simply left the planet after collecting his reward.