Summon Overlord

$?s137044[Spending a Soul Shard on a damaging spell grants Diabolic Ritual for a variable duration. While Diabolic Ritual is active, each Soul Shard spent on a damaging spell reduces its duration by a variable amount sec.][Casting Chaos Bolt, Rain of Fire, or Shadowburn grants Diabolic Ritual for a variable duration. If Diabolic Ritual is already active, its duration is reduced by a variable amount sec instead.] · · When Diabolic Ritual expires you gain Demonic Art, causing your next $?s137044[Hand of Gul'dan][Chaos Bolt, Rain of Fire, or Shadowburn] to summon an Overlord, Mother of Chaos, or Pit Lord that unleashes a devastating attack against your enemies.