New X-Men Vol. 1: E is for Extinction
Grant Morrison (Writer), Frank Quitely and Ethan Van Sciver (Artists)
Sixteen million mutants dead...And that's just the first step in Cassandra Nova's genocidal plans. With an army of evolved Sentinels primed for annihilation, Nova will stop at nothing to see every mutant exterminated from the planet.
New X-Men #114-117, Annual 2001