One of the most famous exclamations in the Marvel Universe is the Incredible Hulk's boastful claim that he is "the strongest one that there is." Whether that is actually true is debatable, but what's certainly not up for debate is the fact that the Hulk is clearly very, very strong. How else could he absorb hits from a god like Thor or take a beating from the Abomination? However, there have also been a number of Hulks over the years, so when we hear "the strongest one that there is," which "one" are we talking about?

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Here, then, we will count down the physically strongest Hulks of all-time. While we will be including alternate Hulks (like She-Hulk and Red Hulk), a large portion of the list is different versions of the classic Bruce Banner Hulk. We're only counting alternate reality Hulks if they ended up on the regular Marvel Universe at some point. Otherwise, alternate reality versions of the Hulk do not count (so no Marvel Zombies Hulk, for instance). So with all the rules laid down for you to follow, we present 15 of the Marvel Universe's strongest versions of the heaviest hitter that the Avengers have on their roster.

15 GRAY HULK

When the Hulk debuted 55 years ago in Incredible Hulk #1 (a series that initially only lasted six issues!) by Stan Lee, Jack Kirby and Paul Reinman, he was not green but gray. Not only was he gray, but he was a completely different type of creature. He was less of a hulking monstrosity so much as he was a sort of a crafty wiseass. He was definitely strong, but not like we're used to.

During the mid '80s, the Hulk became gray once more. During this time, he was thought to be killed, but instead showed up working as a mob enforcer in Las Vegas. During this era, the Hulk faced off against the Thing, with much of the fun coming from the ratcheted up strength of the Thing, so the Hulk/Thing dynamic was reversed, with the crafty Hulk having to deal with a more powerful Thing.

14 SHE-HULK

When it comes to Hulks, the one who got the best deal with becoming a gamma-powered monster was definitely Jennifer Walters. She was dying when her cousin, Bruce Banner, saved her life through a blood transfusion. The transfusion, however, ended up giving her enough of a dose of Gamma radiation that she transformed into a She-Hulk. After struggling with controlling her new powers, she ultimately got so used to them that she stopped changing back into her human form.

She-Hulk is definitely very strong, but in the world of the Hulks, She-Hulk has always been a little bit on the lighter side of things. A big part of this is that she is so adjusted that her powers don't fluctuate based on her anger, which puts her at a disadvantage against the other Hulks.

13 RED SHE-HULK

red she hulk

The fact that Jennifer Walters has been such an adjusted character (although recently, she has been dealing with Post-Traumatic Stress Disorder after almost dying in a battle with Thanos during Civil War II) likely speaks to why the Red She-Hulk is stronger than the regular She-Hulk. Betty Ross was in a catatonic state when the Leader brought her back to life by subjecting her to a procedure that transformed her into the Red She-Hulk.

Much like the classic Hulk situation, Betty and the Red She-Hulk began to view themselves as independent personalities, and as such, the rage of the Red She-Hulk possibly fuels her powers to a certain extent (much like the classic Bruce Banner Hulk). Whatever the reason for the difference in strength is, the Red She-Hulk is stronger than the original She-Hulk.

12 RICK JONES HULK

During John Byrne's brief run on Incredible Hulk, he had Bruce Banner finally separate himself from the Hulk seemingly for good. However, it soon became evident that the two literally could not live without each other. While he was separated from the Hulk, Banner finally married Betty Ross. Their old friend, Rick Jones, showed up for the wedding and hung around afterwards.

When Banner and the Hulk were attempted to be merged together, Jones somehow ended merged with the Hulk instead. His tenure as the Hulk was relatively brief, so it's hard to tell just how strong he was, but he seemed basically as strong as the classic Hulk's base power levels. As we will learn later, though, that is the big demarcation point in the world of the Hulks and strength levels (many Hulks don't stop at "base" levels).

11 SKAAR, SON OF HULK

After accidentally landing on a gladiator planet (the Illuminati meant to send the Hulk to a peaceful planet but when the rocket they built was knocked off course, they were too busy with Civil War to notice), the Hulk slowly conquered the planet and married one of the natives of the planet. Then the rocket Hulk traveled in exploded, seemingly killing his new wife. As it turned out, she survived long enough to give birth to two sons.

One of the sons, Skaar, had much of the same powers as the main Hulk, only he had powers from his mother, as well, including an ability to tap into the elemental "Old Power." When it came to strictly strength, however, Skaar seemed to be slightly less powerful than his old man (Iron Fist was able to knock him out!).

10 SAVAGE SHE-HULK

The new Savage She-Hulk was Lyra, daughter of the Hulk and Thundra from an alternate future. She was sent to the past to find a mate to help save the future of her people, but instead ended up deciding to stay in the "past" and work as an agent for the inter-dimensional safeguard organization known as A.R.M.O.R.

At her base power level, Lyra was weaker than almost all of the Hulks on the list, but unlike the classic Hulk, who got stronger the angrier he got, Lyra was the opposite -- she got stronger the calmer she got, so she developed a sort of zen relaxation method that allowed her to increase her strength by a great deal, leaping her over the other Hulks on the list.

9 THE MERGED HULK

After living as the Gray Hulk for a while, the classic version of the Hulk began to creep in and show up at shocking instances. Eventually, through the help of Doctor Leonard Samson (and the famous hypnotist, the Ringmaster from the Circus of Crime), Bruce Banner was able to reconcile with the other Hulks within his mind. They all merged together to form a composite Hulk who had the strength of the Green Hulk, the attitude of the Gray Hulk and the intelligence of Banner.

The issue, though, is that now that Banner was in control, he refused to let go and that desire kept him from fully accessing all of the power he had at his fingertips. Instead, when he finally let go of all of his anger, he instead transformed into a "savage" version of Banner himself!

8 TOTALLY AWESOME HULK

A longtime friend of Bruce Banner and the Hulk, the young genius, Amadeus Cho, saved his friend Banner by essentially absorbing the Hulk radiation from Banner and taking it on to himself, thereby transforming into the new Hulk (or the "totally awesome Hulk"). Along with his sister, Maddy, Amadeus has begun to hunt down dangerous monsters as the Hulk (while Maddy has to worry about whether her brother will lose control like Banner did).

Unlike the merged Hulk, Cho does not have an artificial limit on his rage, but at the same time, it is unclear if Cho has the precise same upper limits as the original Hulk either. Cho might deserve to be higher on the list in the future, but for now, he places just after the Merged Hulk.

7 WAR HULK

The concept of base levels is a fascinating one with Hulk, as this brings us to the short-lived "War Hulk." During the "Onslaught" event, Hulk was split into two beings, with Banner going to another Earth and becoming the Hulk there while the Hulk remained on Earth, giving off serious amounts of radiation and seemingly being devoid of Banner. The Hulk was then taken in by Apocalypse, who gave the Hulk special armor and augmented his strength and made him one of his new Horseman -- War!

Now, due to him getting the strength increase, War Hulk is obviously a powerful character. However, since he was also under the control of Apocalypse, then while the base level is higher, the upper limits are also capped out, so War Hulk is surprisingly low on the list.

6 RED HULK

The Red Hulk made a huge splash when he debuted by taking on some of the most powerful beings in the Marvel Universe and repeatedly beating them up! This shocked a number of readers, but eventually, it was revealed that there was a very good reason for the Red Hulk's surprising success. You see, unlike other Hulks, he had an additional power -- he could absorb energy from people. So, say, he was fighting Silver Surfer -- he would be absorbing the Power Cosmic as they fought, thus increasing his strength and decreasing Surfer's power.

That made the Red Hulk very formidable, but he learned in a re-match with the classic Hulk that old Hulk's power levels were too much for him, as the classic Hulk's strength was increasing quicker than the Red Hulk could drain his power from him (he also then lost the power entirely due to Doc Green).

5 DOC GREEN

The mysterious organization known as the Ancient Order of the Shield tried to kill Bruce Banner, but after shooting him in the head, his healing powers managed to help him survive, but the healing power was having a hard time fixing the complicated brain patterns of Banner, so Tony Stark helped him by giving him the Extremis virus. The virus healed him but then also gave him a new personality known as "Doc Green."

Doc Green was similar to the Merged Hulk, but he did not have the same self-imposed restrictions on cutting loose, so he should be at a higher level of strength an the Merged Hulk. However, Doc Green realized that the lack of limits was a bad thing, as he might become a villain, so he had the Extremis removed and turned down any further Extremis upgrades.

4 CLASSIC HULK

Silver Age Hulk lifting rubble

After mutating past his gray form (and also transferring from a "turn into the Hulk at night" set-up to "turn into the Hulk when Banner gets angry" set-up), the classic version of the Hulk was introduced. This green version of the Hulk was the first one to claim to be the strongest one that there is, and he sure seemed to back it up over the years.

It was this version of the Hulk that established the classic "the angrier the Hulk gets, the stronger he gets." As a result, there is almost no limit to how strong the Hulk can get. The issue, though, is that the classic Hulk, while obviously quick to anger, is so simple-minded that it is difficult to get him so angry that his strength would hit the upper limits of his strength. He was just too easy to distract and calm him down.

3 MAESTRO

The person that Doc Green was afraid of becoming was the Maestro. In the famous Peter David and George Perez miniseries, Future Imperfect, the Hulk was taken into the future where a crazed older version of himself had taken over the world and killed all the other superheroes on the planet. The Hulk defeated him only by tricking him on to Doctor Doom's time machine and sending him back in time to the explosion of the Gamma Bomb. Maestro was saved, though, during the recent Contest of Champions, so he is running around somewhere.

The Maestro gained enhanced strength from being exposed to radiation for so many more years and also, his insanity helped to drive him to anger further, making him stronger than a standard Hulk. He beat up the Merged Hulk easily. However, his madness also seemed to artificially limit the upper limits of his rage.

2 MINDLESS HULK

Since the Hulk's upper strength levels are based on him getting angrier and angrier, it is only logical that he would need to have a fully functioning brain to achieve that result, and yet, as it turned out, the answer seems to be the opposite. During the period where Banner and the Hulk were separated, the Hulk was completely mindless.

However, as it turned out, rather than having the effect of slowing down the Hulk's anger, the lack of a mind just kept him from controlling his anger at all. He became purely a beast without any burdens, and as such, his anger was headed to astronomical levels. "Luckily," this tends to be a temporary situation, as Hulk and Banner tend to be unable to survive without each other, and while the Mindless Hulk hits peaks that other Hulks cannot get to, it's only for a short period before he falls back down to Earth (and must be re-merged with Banner or they die).

1 GREEN SCAR

As noted earlier, the Hulk's fellow superheroes in the mysterious Illuminati tricked the Hulk into getting on to a rocket that was meant to go to a peaceful world. Instead, he landed on a gladiator planet which he took complete control of, using his gladiator name, "The Green Scar." After the Hulk was seemingly at peace, everything was ruined when the rocket he was sent in exploded. He was told it was sabotage by his old friends.

This enraged the Hulk, but this version of the Hulk had enough mental capacity (his intelligence fluctuated throughout the late 1990s and the 2000s) to remain intelligent while still unleashing all of his anger. This led to this version of the Hulk almost destroying the entire world -- that's how powerful he was when he came back, looking for revenge, in World War Hulk.

We're sure that you have some alternate thoughts on the rankings. Who do YOU think belongs in the top spot? Let us know in the comments section!