Complex sentence: Healers are quite different from the Druids and the Clerics they don't have the supernatural abilities or the fighting skills of these two, instead they are experts in the arts of healing as the Wizards in the arts of magic.
Split into simpler sentences: Healers are quite different from the Druids and the Clerics in that they don't have the supernatural abilities or the fighting skills of either. Instead they are experts in the arts of healing as the Wizards in the arts of magic.