While the Hulk is a product of grizzly mutation made possible by scientific experimentation the likes of which fans would only see in science fiction, his absolute grossest ability has nothing to do with science but is actually based entirely on magic.
Bruce Banner became the Hulk after he was exposed to an explosion of gamma radiation during a test conducted by the U.S. government. After he was engulfed by the radiation which merged the gamma with his very DNA, he was granted the ability to transform into a green, hulking monster anytime he became angry or stressed. However, this super power wasn’t the only change Banner experienced after his gamma exposure as he also gained access to the mystical Green Door which led to a hellish dimension known as the Below Place–the true source of Hulk’s power and immortality.
Related: Hulk's Son Has the Perfect Power Combo to Become the Ultimate Superhero
In Immortal Hulk #8 by Al Ewing and Joe Bennett, the Hulk has been captured by a secret government task force who are holding him in a secure location known as Shadow Base. Since the Hulk is strong enough to break through any containment, the scientists at Shadow Base decided to dismember the Avenger and place each piece of him in separate jars. The Hulk, being immortal, isn’t killed by this and remains fully conscious. Not only is his mind still alert, but he retains control over his severed limbs despite them being cut off from his brain–proven true when he snaps the fingers of his dismembered hand with enough force to shatter the separate jars he is kept in, allowing him to merge his body into a single being once more.
While it makes sense that the Hulk wouldn’t be killed even after being chopped up since his superhuman power
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