Ever since was created all the way back in 1939, they've been treating fans to thousands upon thousands of stories, characters, places, and concepts..Sometimes, things fade into obscurity—only to be known by hardcore fans.

This obscurity doesn't keep the likes of from inserting and using these characters, stories, etc. in their . Not only is it awesome for said hardcore fans to see something so unknown come to life and be utilized, but it opens up the to general audiences. . When the MCU brings these things to the table, things become unique compared to what the general audience thinks is going to happen.

Back in the very early days of the God of Thunder's comics, he actually took up a mortal secret identity. Marvel Comics eventually gave this up in later years and hasn't ever really used it again outside of references. .

He would turn the magical hammer into an umbrella to keep people from asking about why Donald Blake carries a weapon around everywhere he goes. This was referenced when Thor () visited Earth with Loki () while looking for Odin () in . It was a fun little nod to early Thor comics and added some comedy to .

When Tony Stark () needed to replace his suit's A.I. in – due to J.A.R.V.I.S. () becoming Vision– a couple of other A.I. chips were lying around on his desk. One of said chips was labeled "Jocasta", which is actually a deep cut for comics fans, as .

This was . But for those who caught it and knew the comics, this was an awesome little hint at deeper lore for Ultron (). This also hints at the idea that Jacosta is still out there somewhere and could eventually make a comeback one day. Who knows?

The first action sequence of is one of the best in the MCU. Somehow, in this super-serious that takes heavy inspiration from political thrillers, the directors, and , managed to slip Batroc the Leaper of all villains into the opening.

. With a heavy French accent and wild robbery methods, Batroc is a villain no one would ever guess made an appearance in a movie like Captain America: The Winter Soldier. While he lost the "the Leaper" part of his name and is far more serious, the Batroc found in the second film is still an agile villain, which is a fun nod to his comic book counterpart.

The Eternals themselves were already pretty deep cuts from the Marvel Comics world. So, when they added yet another, even deeper cut in Pip the Troll. that appeared in the post-credits scene of .

Brought to life by , before they freaked out seeing . First appearing in Strange Tales #179 (1975), Pip was actually involved in some pretty big conflicts in the books. While he fell to the wayside in comparison to the bigger Marvel heroes, he's been part of some of the biggest fights against even .

Due to being such lower-tier Marvel Comics characters (in popularity) before they made their big debut in 2014, most people don't really know anything about their history—general audiences, at least. A fun fact for many is that Star-Lord () and his team are actually not the first Guardians team to appear in Marvel and a fan-favorite movie character was a founding member!

The Guardians of the Galaxy first made their debut in Marvel Super-Heroes #18 (1969) and consisted of the heroes: Charlie-27 (played by in the MCU), Martinex (played by in the MCU), Major Vance Astro (not in the MCU, yet), Starhawk (played by in the MCU), Aleta Ogord (played by in the MCU), Nikki Gold (not in the MCU, yet), and none other than MCU favorite, Yondu Udonta (), himself. Most of these heroes, clearly, already exist in the MCU and the fact that they were .

One of the biggest in the comics is that their power-sets are actually quite different. While bulks up and gets stronger the angrier he gets, . The radiation within him quite literally radiates out of him and gets hotter and hotter—so much so that he can overheat. His origin in the comics is quite different, too, but it's because he was intentionally turned into the Red Hulk and embedded with Cosmic Radiation that he got such a different power-set.

This was, obviously, not the case with his origin in , . When he is Hulking out, his clothes quite literally burn off of him and his hand burns the carpet of the White House podium. This effect has never been shown off with Bruce Banner () and is a minute but fun way of nodding at his old powers.

As stated, Eternals was already led by a cast of characters that was quite niche as it is. However, when they decided to tease the true comic origins of 's character, the Black Knight. This hero is a very niche one in the comics. Based on Aurthurian legend, the Black Knight wields a sword called the Ebony Blade, . This curse slowly but surely corrupts the user as they use it by feeding and absorbing their negative emotions.

This character is super-powerful and, while not known by general audiences, has come across and aided multiple Marvel heroes and been in a good handful of crossover events. Specifically with characters like (who was featured in the end-credits scene with Harrington) and . . It's Kit Harrington!

While Johnny Storm may be the most popular Human Torch (and known as the only, for some), many people have no clue that he is not the original version of The Human Torch. Also known as , Captain America and Namor the Sub-Mariner (). He was already considered niche and obscure by the 1950s, but he's a genuinely cool character.

While he may currently be featured in in the comic books, he was hinted as far before this in . Being displayed in a case at the Stark Expo that Steve Rogers () and Bucky Barnes () are attending, .

.He's the first non-Norse character to ever wield Mjölnir and is a massive fan-favorite that hardcore Marvel fans have been asking for to be integrated into the MCU for years. He's definitely the most popular of the "obscure Marvel characters" category, but obscure nonetheless.

He was hinted at in Thor: Ragnarok on the giant monument dedicated to all the Grandmaster's () previous champions. While this was an awesome Easter egg, it had people worried that maybe he was dead, due to Hulk being the current champion. This answer was left unanswered. . Maybe he escaped?

While ridiculously underutilized, Gorr the God Butcher () is an awesome villain for the short time he's actually in . His sword, All-Black the Necrosword, may just seem like a god-killing blade in the movie, but for those who are more into the Marvel Comics world, it has so much more depth than one would think. It's actually connected to Venom's lore!

Thanks to , audiences now know about the almighty deity that rules over the symbiotes (Venom, Carnage, etc.) and the character is deeply ingrained in Gorr's lore. and, after losing it in battle, the "God Butcher" came into contact with it and began his quest. This means that Marvel Studios actually has an opening to introduce symbiotes into the MCU if they want to.

NEXT: It All Leads to Doom: Every Confirmed Character in 'Avengers: Doomsday,' Ranked