Gargouille was a member of a faction of Acolytes led by Exodus who participated in an assault on Wundagore Mountain in the European country of Transia, home of the enigmatic scientist known as the High Evolutionary. The Evolutionary had developed a powerful mutagenic compound known as Isotope-E, which the Acolytes coveted for themselves.
Gargouille retained her mutant powers after M-Day.
When the X-Men were looking for Exodus in order to find Sinister's Marauders he had recently joined, they assaulted the former Acolytes who had refused to follow him: Neophyte, Projector, Vindaloo and Gargouille. They were defeated and Projector then answered Logan's question about Exodus' current location.