You have a 10% chance for your Shadow Word: Pain and Mind Flay spells to grant you a Shadow Orb each time they deal damage. Casting your Mind Blast or Mind Spike spell consumes all Shadow Orbs, increasing damage of that spell by 10% per Shadow Orb, and granting 10% increased damage on your periodic Shadow spells for 15 sec. You can have up to a maximum of 3 orbs.