Chaos damage isn't very good anymore. Chaos damage used to be the lowest resist of the target hit, but then was changed to be random damage. So it can be phys, fire, poison, cold, or energy. Physical and Energy are typically the damage types you would want to avoid using, since elves naturally have 75 energy (65 cursed) and there is no way to reduce a target's physical resist. Outside of new tiger's shred armor ability and MAYBE runebeetle armor corrosion ability, which I don't remember if it affects Physical, still though not reliable.