Thor is one of the most powerful characters in the Marvel Universe. He is the God of Thunder, one of the founding and strongest Avengers, and a millennia-old being with enough fighting experience to fill a library or two. Thor truly earns the "Mighty" descriptor.

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However, there are some characters that can overpower even the Mighty God of Thunder. There are foes and even friends who have brought the Thunder God to his knees. Even an immortal being has mountains that he cannot conquer, and the Marvel Universe is full of entities that even Thor must be wary of.

10 Michael Korvac Has Never Been Taken Down By Thor

Michael Korvac Avengers

One of the Avengers' earliest and most dangerous missions brought them into the path of Michael Korvac, a cyborg from Earth's far future with the powers of a god. Both the Avengers and the Guardians of the Galaxy sought to bring down Korvac, and all perished save for Moondragon. She was able to break through Korvac's telepathic defenses and convince him to resurrect the Avengers.

Korvac has returned since then, but Thor once again found himself unable to conquer this being of pure energy.

9 Ghost Rider (Johnny Blaze) Once Stopped Thor In His Tracks

Ghost RIder feature

The Avengers once fought the Champions of Los Angeles--a wonderfully oddball team made up of Hercules, Black Widow, Darkstar, Ghost Rider, Iceman, and Angel. Ghost Rider was on a rampage at the time, and this insighted the showdown. Ghost Rider was able to lay out the Avengers on his own, Iron Man and Thor included. Angel calmed the Ghost Rider down before the fight went much farther.

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Ghost Rider has shown himself capable of incredible power in more recent years, most notably withstanding the Hulk at full strength during World War Hulk and even collapsing a skyscraper onto the Jade Giant by shredding its base with his chain. It's not too far-fetched to think that Thor would be found wanting if he faced the Ghost Rider again.

8 Bor Burison, Thor's Grandfather, Once Returned And Laid Out Thor

Thor VS Bor

Bor Burison, grandfather to Thor, was once brought to the present by Loki and fooled into believing that Thor was a demon. Thor, armed with the Odinforce, faced off against Bor but was utterly outmatched by his grandfather.

Thor was only saved by calling out for help from the Avengers. Unfortunately, at this point, his help came in the form of Norman Osborn and his Dark Avengers.

7 Scarlet Witch Has Fended Off The God Of Thunder Without Falling

Scarlet Witch

The Scarlet Witch has yet to take Thor on in a one-on-one fight, but her reality-warping powers certainly makes one wonder who would win in such a bout.

That said, the Red Skull once brainwashed Thor into attacking his fellow Avengers, and the Scarlet Witch was able to unleash massive blasts of magical energy to send Thor flying into the sky before help came along support her.

6 Emma Frost Once Embarrassed Thor With The Power Of The Phoenix Force

Emma Frost As Phoenix

When the Avenger stook on the X-Men, Thor was at one point alone in a fight against Emma Frost, who was powered up by the Phoenix Force. Thor seemingly had the advantage and shattered Emma Frost's diamond form.

However, the diamond shards flew into the sky and rained down in a flaming diamond meteor shower, knocking out the God of Thunder.

5 Thor Has Yet To Conquer His Father, The Almighty Odin

thor vs odin

Odin is the bearer of an ancient power named after the current king of Asgard-- the Odinforce. Several times over the years, Odin has found Thor to be an unruly son and brutally reprimanded him.

These days, Odin is a shadow of his former self, and Thor is the bearer of the Thorforce and king of Asgard. Were they to square off again, Thor would most likely be able to finally conquer his old man.

4 The Immortal Hulk Has Yet To Be Beaten By Thor

Immortal Hulk

Hulk has been beaten by Thor several times over the years, but the status quo for the Hulk has changed with the coming of Immortal Hulk by Al Ewing and Joe Bennett. The Hulk's strength and powers have expanded, and he is incapable of dying.

The entire Avengers team, Thor included, have taken the Immortal Hulk on twice now. The first time, Thor had a hammer weaker than Mjolnir and was easily laid out by Hulk. The second time, Thor had Mjolnir again, but the Hulk almost suffocated him by regrowing his amputated arm around Thor's head. The God of Thunder had to be saved by the Black Panther. Admittedly, Hulk had backup this time in the form of Harpy, She-Hulk, and Gamma Flight, who kept the likes of Captain Marvel and Captain America busy.

3 Thor Has Never Beaten Gorr The God-Butcher Alone And Lived

Gorr The God Butcher attacking Thor

Thor has fought Gorr the God-Butcher twice as far as readers know. The first time, the power of Gorr proved so great that it took three different Thor's from different points in the time stream to stop Gorr from using the Godbomb to wipe out all gods in all of time and space.

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The second time, Thor and Loki took on Gorr the God-Butcher at the very end of existence, and it took all of King Thor's incredible might to slay Gorr for good. In doing so, Thor expended all of his energies and perished, and he hastened the end of the universe by shattering the pillars of creation (a beautiful figurative expression used by Jason Aaron).

2 Knull, God Of The Symbiotes, Absolutely Laid Out Thor

Thor VS Knull

When Thor finally faced Knull, God of the Symbiotes, in King in Black by Donny Cates and Ryan Stegman, it seemed likely that Thor would be able to conquer the dark god. In fact, Knull and his symbiote dragons have a unique weakness to electricity.

For a time, it seemed like Thor could win, as he even broke of Knull's jaw. However, Knull returned the favor by stabbing Thor with All-Black, the Necrosword, leaving Thor incapacitated and Knull the victor.

1 Thor Has Never (Technically) Conquered The Mad Titan Thanos

Thanos Beating Thor

Thor once conquered the Mangog and Thanos back-to-back in an impressive victory against two of the universe's strongest beings. However, this was later retconned by writer Jim Starlin, who revealed that this Thanos was a wayward drone sent out into the universe by the true Thanos.

When facing the real deal, Thor has always been found wanting. The first time, Thor (then Eric Masterson) was reduced to glass and shattered by a Thanos armed with the Infinity Gauntlet. More recently, Thor fought Thanos at the climax of the Infinity tale by Jonathan Hickman and Jim Cheung, and Thor unleashed the full power of his lighting on Thanos. Thanos was unimpressed and beat Thor into the ground.

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