In the early, chaotic days after the Darkness fell, a wizard whose name is lost to time used a magical staff to summon a fire elemental to protect him from a lich. The lich, who would take the name “the Haruspex,” was a former rival of the wizard. He foresaw the coming calamity, and had transformed himself to better survive the Darkened world. In their battle, the lich assumed control over the fire elemental, the fire elemental killed his summoner, and the lich had a new pet.
The lich feared and respected fire, and thought he could control the elemental better if he subjected it to intensive negative energy. He twisted the elemental Pyralis into a horrifying entity he called a necromental. Together they ruled a small corner of Karator by terrible force, until he was defeated by Rhodri Fawr, a high priest of Syreth. Rhodri destroyed the phylactery of Haruspex, destroying every remnant of the lich.
But the priest recognized that, if he destroyed Pyralis, the necromental would return to the elemental plane from which he came as an undead fiend, creating more of its kind. So he assumed control over the elemental, and kept Pyralis under leash by the magical staff that first brought it to Karator, until the Gaol could be constructed.