Following the Inferno crisis, the United States Army founded Project Purgatory to research the fields of the supernatural and paranormal. One of the recruited scientists, Doctor Noc, developed technology to use the X-Gene-Positive infants N'astirh kidnapped and the New Mutants and X-Terminators delivered to them to open portals to Limbo. General Ulysses, Doctor Noc, and a trained band of military soldiers established a military base in Limbo, the Hatchery. At the base, they continued to experiment, both on demons and on the Inferno babies, and train new soldiers. However, when they recovered the Bloodstone amulet, the base was attacked by Witchfire and the Inferno babies were believed dead. The Earth based military forces sealed off the portal Epsilon, leaving those on the Limbo base stranded to find the observation portal with virtually no hope of escape.
After 26 years in Limbo but only 4 years on Earth, Noc and Ulysses were able to locate a traveling portal and return home. However, they never gave up their mission of taking control of Limbo and capturing Illyana Rasputin. They returned to a world where all of the mutants were living together on Utopia and, therefore, their commanding officer, General Combest, ordered them to stand-down. The unit still believed that Illyana was a significant threat and, by order of General Ulysses, they kidnapped Pixie. Upon return to their base, the Inferno Babies were revealed alive when they killed General Combest and obliterated the entire battalion. The New Mutants showed to rescue Pixie and the Inferno Babies defeated them. After Dr. Noc and General Ulysses took Illyana's Soulsword and Pixie's Souldagger, they extracted the Bloodstones and completed the Bloodstone Amulet to call forth the Elder Gods. They, along with the Inferno Babies, tortured the New Mutants and took them to Limbo to use as a sacrifice for the Elder Gods. Once they returned to Limbo, the Demons Three asked them to turn over the Bloodstone Amulet and General Ulysses had them beg for mercy, then killed. After releasing the Elder Gods, General Ulysses was killed attempting to control them and the group fought against a demon horde. Dr. Noc ordered a retreat and Cannonball destroyed the escape vessels.
- 14 members of Project Purgatory (Earth-616)
- 7 appearance(s) of Project Purgatory (Earth-616)
- 1 minor appearance(s) of Project Purgatory (Earth-616)
- 3 image(s) of Project Purgatory (Earth-616)