Ancient Scarabs chase the enemy and use poison storms that can paralyze or poison players as well as poison missiles. They will fight until death, and can retarget.
Larva's final stage and this stage starts with larva then scarab then Ancient Scarab. They are almost as powerful as a Giant Spider, but can be more dangerous since they can paralyze you. It is not uncommon to get 2 or 3 on you at once in the Larva Caves.
A hunting team should consist of a single blocker and one or more shooters. Paladins with Distance Fighting of 65+ are welcome. Mages should attack using a Rod/Wand, together or optionally with summonedDemon Skeletons, Flame Strike, or Fireball/Icicle runes. In case the team decides to use Demon Skeletons and there is no Druid, or the druid is not yet on the required level to mass heal on the Party, don't forget to bring some IHs to heal the Demon Skeletons from time to time. Low level blockers should consider wearing a Silver Amulet to reduce part of the Poison damage received when hunting Ancient Scarabs. A Sorcerer with a blocker can hunt these easily and get a lot of experience in a short amount of time. The Knight lures 2+ Ancient Scarabs then the Sorcerer uses Fire Wave to kill. Druid can use this tactic too by using Ice Wave. A high level mage can also block healing with just exura, Fire Walls can also be shot to make sure the ancient scarab doesn't switch to the shooter.
Mages Since the update, Fireball runes can be used to kill these creatures effectively. A 50+ mage can solo Ancient Scarabs rather easily by running them and hitting them with Flame Strike. High Magic Level is recommended. Always keep Exura handy in case you get paralyzed. You should be ready to heal if your HP goes under 300, since otherwise you can die by an unfortunate combo. If more than 1 Ancient Scarab is lured, then you should use GFBs or Avalanches to kill it fast, since 2 at a time can kill you in the blink of an eye. You should also keep some GFBs or Avalanches handy in case you get two or more larvae or scarabs on you which will break your shielding. Druids can hunt these as soon as they are able to cast the Mass Healing spell: summon two Demon Skeletons, get a strongest Rod (i.e Hailstorm Rod) ready and attack the target; heal the DS on low hp with Mass Healing. High LevelSorcerers can hunt these using Energy Wave to kill 2 or 3 at a time. Mid to High LevelSorcerers can also lure large amounts of Ancient Scarabs to the stairs before using Hell's Core, gaining large amounts of experience at once, though there is relatively high risk.
To lower earth damage you receive you can wear some parts of Terra Set and a Silver Amulet.
Knights May hunt these solo at the same level you would hunt Giant Spiders, but only at higher levels will get profit out of the hunting because of their resistance to physical attacks. High Level knights can lure some Ancient Scarabs and finish them all off with Exori's. Most damage a knight will receive is from the Poison.