He-Man has been referred to as the most powerful man in the universe. By the power of Grayskull, indeed. He has thrown mountains at his enemies to take them down, which seems like a wildly over the top way to make a point. Still, the power He-Man receives from the Sorceress of Castle Grayskull is undeniable. His power is so impressive that it actually allowed him to take on Superman at one point. But that's the DC Universe. In the Marvel Universe, there is a whole roster of characters for He-Man to face, some that he could beat and others that would take him down.
10 LOSE TO: Silver Surfer
Galactus did not create the Silver Surfer to lose a fight with He-Man. The Surfer can fly at great speeds thanks to his surfboard, has incredible strength and endurance, and can generate powerful cosmic blasts. But the Power Cosmic given to him by Galactus is so much more than that. He can manipulate solid matter. He can create black holes. He can destroy planets. If He-Man could get the Silver Surfer on the ground and mitigate his power somehow, such as what the Sakaarans did in Planet Hulk, he might stand a chance. Hopefully, Man-At-Arms is cooking up a plan or He-Man is losing this one.
9 DEFEAT: Hercules
The Son of Zeus is known for fantastic feats of strength and heroism. Well, that's what he likes to tell you over a few pints, at least. It's not that he isn't powerful and hasn't done incredibly heroic things but he also loves spinning a great story. Hyperbole might be his greatest superpower. This is probably He-Man's best one-on-one matchup in Marvel as the two men have very similar power sets, including strength, invulnerability, and speed.
Ultimately, He-Man wins this fight thanks to the well of power he draws on from the Sorceress. It would allow him to outstrip the power Hercules wields. Plus, there's a solid chance Hercules wouldn't be sober enough to put up a decent fight.
8 LOSE TO: Thor
As an Asgardian and a member of the Avengers, Thor has long been one of the greatest heroes Marvel has to offer. Mjolnir gives him incredibly vast powers that make him a more than formidable opponent for anyone around, including He-Man. While they match up well in strength and experience as warriors, they don't match up in signature weapons. Like Thor, He-Man's power comes from his weapon, which is the Power Sword. As impressive a weapon as it is, the Power Sword does not compare to Mjolnir. He-Man could take some of the punishment that Mjolnir could dish out but it would eventually overwhelm him.
7 DEFEAT: Adam Warlock
Marvel's resident astral sorcerer seems to change abilities as often as he changes sides between good and evil. Regardless, Adam Warlock has consistently proven to be one of the most powerful individuals in the Marvel Universe, and not just because of his abilities. Adam's true powers are his intelligence and cunning, being able to manipulate any situation to his advantage.
Unfortunately for him, He-Man is also intelligent and cunning, and possesses more raw power than Adam Warlock does. He-Man would be able to anticipate any of Warlock's plans and has the strength to overcome them.
6 LOSE TO: Sentry
Sentry was once touted as the greatest hero everyone forgot about. It was an interesting angle for introducing a character so powerful that he fought the likes of the Hulk to a standstill. His internal conflicts aside, Sentry has a level of power that is virtually impossible for his opponents to combat. The man once flew Carnage into space and tore him in half. That only slowed Carnage down for a while but it was impressive nonetheless. He-Man is a powerhouse but the Sentry is someone who could shrug off a mountain being thrown at him. It's hard to imagine He-Man bringing anything to the table that could harm Sentry.
5 DEFEAT: Juggernaut
Once the Juggernaut gets moving, nothing is supposed to be able to stop him. Well, he has been stopped a few times over the years and He-Man is a name that would definitely be added to that list. Juggernaut's powers are mystical in nature as are He-Man's.
But Juggernaut has proven to be vulnerable to mystical swords in the past, such as Shatterstar's. He-Man is strong, fast and has a weapon that is perfectly suited to defeating the Juggernaut. If anyone can stop this guy, it's He-Man and it would be an incredibly destructive battle.
4 LOSE TO: Hulk
The angrier Hulk gets, the stronger Hulk gets and He-Man seems like someone who would really make the Hulk angry. The problem for He-Man in this fight is he might actually be strong enough to stand up to the Hulk. At first. But the longer the fight goes on, the Hulk is just going to get more angry about not being able to take He-Man out. Eventually, he'll get strong enough that He-Man can no longer take the beating. He-Man is capable of taking a lot of punishment but there does come a point that he expends his energy and reverts back to Prince Adam. The only chance he has at that point is Hulk laughing so hard he calms down and changes back to Bruce Banner.
3 DEFEAT: Doctor Doom
Doctor Doom might be Marvel's greatest villain. In the comic books, at least. You wouldn't know it from his portrayals on the big screen. Doctor Doom is as intelligent as Mr. Fantastic, wears a suit of armor as impressive as Iron Man's and wields powerful magic as well as Dr. Strange does. On top of that, he has a whole nation at his disposal and an army of robots.
But anyone who watched the 1980's He-Man cartoon knows how experienced he is at smashing robots. Doom's greatest weakness is his arrogance. He would take one look at He-Man and assume victory, which would prove to be his greatest mistake.
2 LOSE TO: Thanos
Describing Thanos as Machiavellian in his brilliance is an understatement. His goals are always lofty in dark and underhanded ways but still impressive. A lot of villains have tried to rule the universe. Few have ever desired to kill half of all life in the universe and been successful at it. Even without the Infinity Gauntlet, Thanos is incredibly powerful and has vast resources at his disposal. The Mad Titan is a difficult opponent for anyone to face, and defeating him has required some incredibly creative plans. As tough as He-Man is, he has neither the power nor the resources to defeat Thanos.
1 DEFEAT: Iron Man
Tony Stark's career as a hero has been filled with incredible ups and downs. But the one consistent factor has been his armor, and his incredible ability to improve his designs. Stark gets a lot of credit for his intelligence but not enough for his imagination. Unfortunately for him, imagination isn't enough to beat He-Man and neither is his armor. It gives Iron Man such a broad range of attacks that He-Man is more than capable of defending against. Once He-Man gets his hands on Iron Man, he'll crack him open like a can of tuna fish. Unibeams are great until you take a battleaxe upside the head.