Since its release nearly two years ago, Al Ewing and Joe Bennett's horror-inspired take on a longtime Marvel favorite has turned into an instant classic. The Immortal Hulk has given the Hulk a new life in the world of Marvel Comics, and while portraying Bruce Banner at his lowest, he has produced one of the best Hulk storylines to date.

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As you might expect from the brilliant mind of Al Ewing, there's a great deal of depth laced throughout Immortal Hulk. That depth most stems from the way that Ewing has progressed Hulk's story, moving away from making us think he's just incredible but instead immortal. Although Ewing has moved away from the Hulk of the old days, that doesn't mean he hasn't paid homage to them throughout his latest story. In the spirit of paying our respects to both a new classic and an old one, let's take a look at 10 connections to the old Hulk comics seen throughout the first 31 issues of Immortal Hulk. 

10 Xemnu

xemnu

A good deal of the callbacks that Al Ewing has introduced in his dramatic horror story revolves around the reemergence or resurrection of older characters. One of those characters, first teased on the cover of the 30th issue of Immortal Hulk and eventually being introduced even earlier in the series, is Xemnu. Otherwise known as the "Living Hulk", Xemnu is a classic Hulk character first introduced way back in 1960 in Journey Into Mystery #62.

Xemnu's new look from Joe Bennett is astonishing and much needed as he hasn't been seen in some time. He's also the subject of the next two covers for Immortal Hulk, so it might be time to speculate that his role in the series will become even larger. Until we find that out, it's nice for fans of the earlier Hulk comics to see a familiar face.

9 Reginald Fortean

Another older Hulk character making his retitled return in Immortal Hulk is the soldier who was formerly the right-hand man of General Thaddeus Ross. As the series portrayed Ross's death and funeral, it was clear that someone had to have taken over his duties as General.

It should come to no surprise for classic Hulk fans that the person to do so was Reginald Fortean. As the new leader of the United States Hulk Operations, tasked with tracking down Bruce Banner, Fortean returns and in this version, unfortunately, becomes the new Abomination.

8 Absorbing Man

Carl Creel, the Absorbing Man, has been a longtime nemesis of the Hulk. Creel played a massive part in the original Incredible Hulk series, so it only made sense for Ewing to bring him back in Immortal Hulk. In typical Ewing fashion, he reintroduces Absorbing Man in a way that plays into this horror-laced story.

Under the control of the One Below All, Creel appears this time as the "Red Dog". Creel is one of Hulk's most classic and long-standing enemies and his return in Immortal Hulk allowed artist Alex Ross to create an absolutely incredible cover for Immortal Hulk #9 pinning Bruce Banner against the Red Dog.

7 Roxxon

From one of Immortal Hulk's first panels, it was clear that the Roxxon Corporation would be playing some kind of role. Obviously, Roxxon has been a staple in the history of Marvel Comics, and has always helped storylines tackle the issues imposed by a major corporation, something definitely addressed Immortal Hulk.

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While Roxxon doesn't really correlate with some of the very old Incredible Hulk comics, it still has a decently long history with the Hulk and even the She-Hulk as well. No one could've predicted how big of a role Roxxon would go on to play in Immortal Hulk, but up to this point in the series, it's been a welcomed addition to deepening the story.

6 Teen Brigade

One immense nod to the original Incredible Hulk comics was Ewing bringing the Teen Brigade back in Immortal Hulk. The group is, obviously, comprised of teenage Hulk defenders who were originally messengers to certain Heroes. Along with their inclusion in the classic Hulk comics, they also appeared in several early Avengers additions as well.

They're now back in Immortal Hulk and primarily serving as Hulk defenders. They don the mask of the green giant in Joe Bennett's portrayal, first appearing on the cover of Immortal Hulk #28. Although their purpose in the new story is massive, they still are a great nod to classic comics of Hulk's past.

5 Harpy

Betty Ross as Harpy in Marvel Comics

This next one is definitely an unfortunate callback, and especially for Bruce Banner. However, in Ewing's horror tale, it makes perfect sense. Betty Ross has been a staple in Hulk comics from the get-go. However, her demonic and monstrous alter appearance was introduced years later.

Ross' death in Immortal Hulk, right in front of Bruce Banner, led to a brutal Hulk-out and distracted the reader away from Ross. Where her body was, laid a single red feather. Well, that was the perfect teaser for the return of a classic Hulk character, just in a different form. Now red from her days as the red She-Hulk, Harpy is back and playing into the horror that is Immortal Hulk.

4 Nighttime Transformation/Color

While we've addressed plenty of callbacks that have to do with characters of older Hulk comics, we haven't discussed many connections to the Hulks of the past. That is, until now. Thus far in Immortal Hulk, we've seen how this unkillable Hulk's powers have changed slightly. One of the earlier restrictions of the Hulk's power was that the transformation into the Green Goliath only occurred at night, which we've seen is the case for Ewing's Bruce Banner.

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Another callback Ewing introduced in Immortal Hulk that shows respect to the earlier days of the Hulk is that iconic and original grey color. Giving nod to the Joe Fixit, or Grey Hulk, days of the Hulk, Ewing once again shows his creativity and respect for the source material.

3 Rick Jones

For generations, Marvel Comics has introduced and re-introduced the character of Rick Jones in dozens of different series. Well, Ewing made sure to bring him back once again in his Hulk story. Like most things in this story, Jones was brought back in a much different way, reinvented from the original sidekick role of his earlier days.

His new gamma-radiated form gives a fresh take on the previously thought dead character, but his connection to the Hulk and memories of the past prove he's the same Rick Jones that's always been a cornerstone in Marvel.

2 Hulk vs. The Avengers

Although we've gotten used to the idea of Hulk being a member of the Avengers, he's actually just as notable for fighting against them. Since 1964, some of the earliest days of Marvel Comics, the Hulk has been pitted against the Avengers dozens of times.

In Immortal Hulk #7, Ewing pays homage to that classic rivalry by once against setting the stage of the Hulk vs. the Avengers. It's a major part of Hulk's origin and has persisted through all the different iterations of the character. It's a spectacle that anyone would want to see, and Ewing and Bennett's take on it was just as magnificent as you'd expect.

1 His Intelligence

From the jump in Immortal Hulk, it was clear that this version of the character was as competent and intelligent as we've seen. Although some might be used to the Hulk being more than just a mindless and violent monster, his intelligence has much more significant meaning to the character and is actually a nod to similar versions of Hulks in the past. Perhaps a nod to the Doc Green days of the Hulk, Ewing's Hulk has nearly the same intelligence level as Bruce Banner.

These highly intelligent versions of the Hulk are becoming more and more popular, as we've seen in both comic forms and in the MCU. In either form, these versions take inspiration from some of the earliest iterations of the Hulk, and it's hard to imagine a story like Immortal Hulk being possible without them.

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