The Sylron

Also known as The Feytouched, The Sylron are a dangerous order of warlocks, principally eladrin, whose frequent visits to the Feywild have afforded them powers that have driven them beyond the brink of madness. The Sylron developed a ritual that Heradric Dreth'dor used to banish Paen the Mad from the world and trap him in the Shadowfell.