The Reversal of the Decimation was the occurrence in which Bruce Banner wore Tony Stark's Iron Gauntlet. As Hulk snapped his fingers, the effects of Thanos' Decimation on the universe was reversed, with half of its population being resurrected.
As all of the Infinity Stones are gathered back into the present, the Avengers realized Black Widow sacrifice to gain the Soul Stone. Determined to not let Natasha’s sacrifice be in vain Tony Stark, Rocket Raccoon, and Bruce Banner began working on a new Infinity Gauntlet. After the creation of the Gauntlet was complete, Rocket asked who was going to be the one to reverse the Decimation.
At the moment when the Iron Gauntlet was set for completion, Thor volunteered himself to put it on, but the Avengers held him back, saying he was neither physically nor emotionally stable enough to do so.
Bruce Banner volunteered himself, reasoning that as the Stones and his body contained mostly gamma radiation, he was the most likely to survive the use of the Gauntlet. While Tony ordered F.R.I.D.A.Y. to initiate lockdown procedures across the facility in case the Gauntlet's energies proved to be too powerful to contain, an alternate Nebula began to sabotage the quantum device as Banner put on the Gauntlet. The Avengers began worrying for him as Banner channeled the power of the Stones through his body, severely scorching his arm in the process. Thanos' mothership emerged and crashed through the roof of the facility, destroying the quantum device, just before Banner snapped his fingers, bringing everyone who Thanos decimated back.
Ant-Man guessed that the mission of resurrecting the universal population worked as he looked outside at a group of birds that appeared out of nowhere, while at the same time Hawkeye received a call from his wife, who had previously perished in the Decimation. As the group start to realize whether or not their mission had been completed, a dazed Bruce Banner noticed Thanos' mothership from above the window ceiling. Before he could react, Thanos' mothership fired upon New Avengers Facility, destroying it and causing the Avengers to be separated from each other, although Hawkeye is able to take possession from the Gauntlet. The effects of the reversal become apparent during the ensuing battle when Captain America received a transmission from Falcon, one of the victims of the Decimation, and the rest of the resurrected started appearing shortly thereafter through portals created by Doctor Strange and other sorcerers.
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