Maw was one of the mutant babies that was kidnapped by demons during the Inferno crossover. He was used as a means to open a demonic portal from Limbo to earth so that all demons could enter. Luckily, the New Mutants, the X-Terminators, the X-Men and X-Factor intervened to fight of the demon hordes. The New Mutants with the help of the X-Terminators where tasked with bringing the babies back home safely and succeeded. They where brought to a church for safety until the demonic invasion was over. The baby's where brought back to there parents and seemed to be safe once more.
Maw was created by Louise Jones Simonson and Jon Bogdanove and first appeared as a baby in X-Terminators Issue #2 (1988). Years later, he made his first appearance as an adult in New Mutants Issue #16 (2010). This version was created by Zeb Wells and Leonard Kirk.
Mayor Story Arcs
However, unbeknownst to the New Mutants, the government took the babies into their custody. They were passed over to the care of the armed forces who treated the babies as potential weapons. Project Purgatory was formed to take the infants to Limbo where time moved faster than on Earth. In Limbo, the babies were brutally experimented on, often with triangular slices of skin being removed for testing.
Project Purgatory was caught off guard by an attack of Limbo Demons led by Belasco's self-acclaimed daughter, Witchfire. During the attack, the children managed to escape their bonds & fought the demons, successfully killing them all. However, the confused message that was sent out indicated that the children had been killed. Therefore, lost in Limbo with no means to return home, Project Purgatory continued to mould the mutant children into perfect living weapons.
During some down time after the events of the Second Coming, the New Mutants were unexpectedly taken into Limbo by Magik. She could sense that Pixie had been kidnapped, and set out to save her. However, Magik & the New Mutants were attacked. The mutant children had spent the last 20 years living in Limbo, and they had learned to attack individually & in a group.