UNCANNY X-MEN (1963) #526

Things have never been worse for the X-Men. They’re stuck in an impregnable dome of Bastion’s creation. As if that’s not bad enough, inside this dome is a portal to the Days of Future Past timeline through which thousands of Nimrod Sentinels are pouring. Cyclops has sent Cable, Cypher and X-Force on a suicide mission into the future to destroy the portal, but do they stand a chance? There is a wall of the dead in the future that includes the portraits of many slain mutants, including Beast, Iceman, Penance, and Wolverine.