What Happened To Every Version Of The Hulk?

Maestro is a version of Hulk from the future, where nuclear war had obliterated half of the Earth, and left those remaining under the fist of the tyrannical green giant.

With the radiation of this war only increasing the Maestro's power further, he proves a colossal threat to anyone trying to fight him - something that our Hulk would learn when he was sent into the future to fight his dystopian self. However, while the radiation improved Maestro's strength, it didn't improve his intelligence, allowing the Hulk to outsmart him and send him back in time to when the first gamma bomb went off, killing him instantly.

But no good Marvel character stays dead long, and Maestro's skeleton would absorb enough gamma radiation over the years to bring him back to life in the current timeline, which will no doubt be used in a future storyline when readers least expect it.