Once known as the Holy Emanations of Shallamar, the Demon Lords of Nil are half-formed entities who were altered by the Taint during Project Cosmic Hope.

Known Demon Lords

Gorgulu, the Devourer of Souls, but was first known as King Gorgaliel, the Peacemaker
Nifilhema, the Queen of Insufferable Cruelty, once King Gorgaliel's Queen of Illustrious Beauty
Luciphage, the Supreme Master of Nil, formerly the Lord of Compassion
Baalphegar, the Prince of the Dark Fates
Ashtorath, the Duke of Inescapable Damnation, no longer the Blessed Lord of the Golden Bells

Special note

Grimbach, the Golden Poet, though a sibling, is not a Demon Lord, having left Shallamar to be with Dumaliel long before the Taint.