Age of X: Universe #1
And there came an Age Of X, an age unlike any other, where there were no X-Men...mutants were hated and feared. In that age, the remaining mutants created a stronghold, a last bastion for their dying race: Fortress X. And in that Age Of X, when humanity vowed to see Fortress X destroyed, a team of heroes and heroines found themselves united against this terrible mutant threat. This is their epoch!