Ultimate X-Men v09 - The Tempest (2005)

Collects Ultimate X-Men (2001-2009) #46-49.
The X-Men have become more than a team. They've become a family. And the death of one of their own leaves the remaining X-Men struggling to deal with the loss. And even before a moment of silence can pass, the mysterious Mr. Sinister arrives, intent on giving the X-Men a lot more to mourn!