Earth-31393 has a duplicated history of Earth-92131 up until the point where the assassination attempt is made on Senator Kelly.

After Senator Kelly was assassinated by Mystique (who was posing as Gambit in order to discredit the X-Men), mutant control laws were passed and an army of Sentinels built. The Sentinels hunted down and eliminated all mutants, including the X-Men, apart from Wolverine who survived and joined the Mutant Resistance, and was later joined by Bishop. Rebellion leader Forge constructed a time machine, planning to send someone back to the 'past' in order to stop the assassination of Kelly. Bishop agreed to go, and in the past he was successful. A new timeline was diverged, but when Bishop traveled back to the future he discovered that the world had been ravaged by a plague.