Well, as the OP learned, they're almost certainly lethal without paralysis resistance.
With it... well, they have decent HP, a powerful melee attack, and are fast enough to run you down with 7lbs (>100 damage per hit against decent PV and 160 speed is typical). I put them on about the same level as werewolf kings. If you try to fight one in melee, you'll very quickly realize this it is an endgame monster and not just something you can mow over. The kind of thing that is probably worth teleporting passed if you find a threat room of them. They're a lot more dangerous than berserker kings, IMHO.
Hoping to win with every class, doomed. Archer, Barbarian, Bard, Beastfighter, Druid, Elementalist, Farmer, Fighter, Monk, and ULE Priest down.