X-Force, Vol. 3: Ends/Means

Fantomex's compulsion to be The Best has caused him to turn on his former teammates! Can a squad of killers hope to escape science's perfect living weapon? Fantomex begins a murderous rampage, taking out each and every one of the world's secret intelligence agencies, working his way closer to X-Force. Knowing the confrontation is inevitable, Cable and his team ready themselves for the fight of their lives. And as X-Force learns the true identity of the villain they have been pursuing for months, Cable hatches one last scheme, and the fate of Hope Summers is revealed! In the final showdown with Fantomex, X-Force will give everything they have to defeat their power-mad teammate-turned-adversary. And in the end, not everyone will emerge unscathed! Collecting X-Force (2014) #11-15.