warlocks and bloodks can solo them afaik, I've seen a fire mage in full hc pve gear killing them faster than my quad box team does (until I killed him and stole the kill ;D)

a 3 hybrid team should have decent gear lets say ~490+, its much easier with a tank and/or heal though

the mechanics of those mobs is pretty simple, kite him away from the spirit, dodge the ground slam, aoe the scarabs and prey for the meteors to miss you