Damage Taken From Elements
Turns Invisible really often and runs away in low health.
This boss often causes death for unprepared players, even high levels, so if you are planning to hunt in Vampire Crypts, always be all ready in case this boss appears. Arachir often hits with paralyze + drunkeness combo, so you should always keep a Dwarven Ring ready in case you need to escape or you try to outrun it.
Mages: A possible strategy for mages would be to lure it to the rope hole while using Mana shield. Then use either Hell's Core (Sorcerers) or Eternal Winter (Druids) to kill this vampire lord and it's summoned Liches.