The Incredible Hulk is a horror character in a superhero world; like Henry Jekyll or Larry Talbot if their alter egos resembled Boris Karloff as Frankenstein's Monster. Ever wonder why Bruce Banner has more alternate Hulk personas than he does memorable external villains? It's because his greatest battle will always be an internal one.

The 50-issue "Immortal Hulk" by Al Ewing and Joe Bennett was one of the defining Marvel comics of the 2010s, in part because it embraced the character the Hulk is meant to be. Ewing added fantastical layers to the jade giant, revealing Dr. Banner had not simply been mutated by the Gamma bomb explosion where the Hulk was born; the bomb opened a "Green Door" to the underworld.

There are two ongoing Marvel comics right now that could be called "Immortal Hulk" sequels. One is Ewing's "Immortal Thor," which features overlapping themes and villains (without...