Complex sentence: Like the Hierophants of the White Order, Druids are also powerful healers, being able to heal not only people, but even the very land itself; their greatest power, however, is their dominion over plant life and water.
Split into simpler sentences: Like the Hierophants of the White Order, Druids are also powerful healers, being able to heal not only people, but even the very land itself. Their greatest power, however, is their dominion over plant life and water.