Warlocks are the most likely to go insane. Some of their helmets are designed to keep the warlock sane (somehow). And the warlock mind rests between godhood and madness. Warlocks might be so against hunters because hunters are the only class that has a chance against a warlock. And that destroys their "godhood". Source: warlock grimoire card, osiris grimoire card, warlock common and rare helmets.