Schemes of the Lich King
Horrible, harbingers of the Diabolist, these act as heralds and servitors to her loyal subjects. Often summoned by her wizards and clerics, these terrible and powerful foes have but a brief time that they can be stopped. If the summoner can be stopped or killed prior to the creature existing on the current plane, they will be sent back from whence they arrived. Otherwise, these vile monsters will roam free, wreaking havoc on all they cross.