How do you use dark crystal on Dragon Fable?

In Dragon Fable, the Dark Crystal is a powerful item that can be used to enhance your character's abilities. To use the Dark Crystal, you must first equip it in your character's inventory. Once equipped, you can activate the Dark Crystal during battles to unleash its dark energy and deal increased damage to your enemies. It is important to strategically time the use of the Dark Crystal to maximize its impact in combat situations.