After his armor underwent a complete system failure, Iron Man survived the near-death experience by getting an upgrade courtesy of Marvel's most powerful hero, Sentry. In Mighty Avengers #11, the Avengers take on Doctor Doom, but when Iron Man gets hit with a powerful energy blast that drains his suit of its power, it forces Sentry to bring it back into action by unleashing his own incredible powers of a million exploding suns at the armor.
The Sentry is in a league of his own regarding the full extent of his abilities, as Marvel's Superman-like hero has the power of one million exploding suns. In addition, the staggeringly powerful hero doesn't seem to have a power limit and, when fully charged, is nearly unstoppable to take down. However, with those fantastic powers comes an uncontained evil side of the hero called The Void, a manifestation of darkness that equals Sentry's capabilities in its destructive nature. Sentry has erased the Avengers and his own memory of his super-heroics to prevent The Void from emerging. But, when Sentry re-emerged and joined the Mighty Avengers, he showed off his incredible powers by supercharging Iron Man's armor and giving him an on-the-fly upgrade.
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In Mighty Avengers #11 by Brian Michael Bendis, Mark Bagley, Danny Miki, Allen Martinez, Marko Djurdjevic, Justin Ponsor, and Dave Lanphear, the Avengers take on a group of Mindless Ones as Doctor Doom messes with the time stream. Doom sets off a neural energy swarm drain, with the explosive blast seemingly killing Iron Man and shutting down his armor. However, after Captain Marvel tries to absorb the energy, Iron Man awakens and tells Sentry he needs to recharge
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