10 Deadliest Comic Book Events

House of M may have marked the biggest loss to mutant kind, but strictly speaking, very few actually lost their lives during the event. The massacre in Genosha a few years early though, now that's a different story.

With the Sentinels decommissioned, the X-Men finally thought they were on the road to recovery. Their positivity wouldn't last long though, as they were about to face one of the biggest disasters in mutant history.

With Cassandra Nova's introduction came the ultimate threat. Nova is hatred personified, having attempted to strangle her twin in utero. She spends her days trying to halt the evolution of mutants and, as far as first attempts go, the villain did a pretty good job.

Cassandra had found a Master Mold deep in the jungle of Ecuador and kidnapped Bolivar Trask's nephew in order to control it. Wolverine and Cyclops are sent to investigate what's happening and manage to take down Nova and a few Sentinel-Bots, but it was too late.

Following her orders, Trask had already sent a group of highly advanced Sentinels to lay waste to the island of Genosha, killing over 16 million mutants in a matter of minutes.