With 65 uncategorized weapon skill, some dexterity, gloves, telecontrol and a wand of teleportation, it's possible to slap enner to death. Sure, it's far from optimal and horribly dangerous especially considering the massive danger level boost hitting level 65 skill gives, but slapping him hard enough to send his head flying is truly worth it.
The scream damage is negated by armor, that I'm sure of. Since I don't play LIVAN, no clue about whether amulet of elemental protection does anything to it. The usual resistance gear probably does nothing against it. Aside from staying at a distance or wearing good armor there aren't any other measures against his scream I'm aware of.