Squirrel Girl.
She bested Iron Fist and Wolverine both (according to Bendis).
Echo and Taskmaster since they both can mimic the fighting styles of anyone.
Breaking this up by the books I read, though I know Iron Fist, Daredevil, and Shang Chi would be in the upper echelons of the best fighter tiers:
X-Verse
Wolverine, Psylocke, Gambit, Domino, Nightcrawler, Storm, Cyclops, Kitty, Cable, and X-23
Avengers Verse
Steve Rogers, Hawkeye, Black Widow, Winter Soldier, Black Panther, Falcon/New Cap, She Hulk, Thor, Mockingbird and Jessica Drew
Misc - FF/Inhumans/GotG
Sue Storm, Doom, Thing, Karnak, Moon Dragon, Drax, Mantis and Gamora
It's not just his power set and augmentations, but his physical attributes that determine Wolverine's fighting style.
I'll say it again, he is only 5' 3". Now take away his mutant powers and enhancements, including healing, greater muscle mass, stamina, longevity, reaction time, etc. He still has to fight close range, because he doesn't have wingspan or reach. His striking area of effectiveness is very shallow. Kicking extends that to some degree, but not by much. Why? His legs are short, too. This is a comic book environment, so I won't bother getting too much into real world dynamics, but trust me when I say that there is a reason why we have different classes and rankings in just about every sanctioned form of martial art sport.
We can only hope that Wolverine as a "normal" human would have peak human speed and uncanny durability, because he's going to get hit often. Usually, characters like that get a weapon, armor, or some type of power to bridge the gap. To Marvel's credit, they did just that.
Puck!!!!!!
“Generally, one knows me before hating me” -Quicksilver
Tyson. Fought mostly all his fights with a height more importantly "Reach" disadvantage.
I find the argument of "take all his powers away" to be moot.
one of his powers... the most important one is the near agelessness. Time of years and practice in fighting. . . both in martial arts and brawling. Is why I rate him the top. or at least IN the top.
Experience + practice
My priority is enjoying and supporting stories of timeless heroism and conflict.
Everything else is irrelevant.
1. Daredevil
2. Shang-Chi
3. Iron Fist
4. Captain America
5. Wolverine
6. Black Widow
7. Moon Knight
8. Karnak
9. Echo
10. Stick
I kinda want to use this thread to talk about something that's all too prevalent in comics (especially mainstream comics): the idea that X or Y character knows or is a master of 100+ or all forms of martial arts. The kind of stuff you've gotten with characters like Captain America, Batman, Black Panther, Iron Fist, Wolverine and Ninjak (and anyone else).
First of all, it's impossible. There are way too many martial arts in the world. Some of them are still in a recovery process and some could be unknown. Not to mention actually finding masters of said martial arts and then finding the time to learn and master them.
And then there's the simple truth that many martial arts aren't useful in a modern day setting, and it makes no sense for certain characters to even know them. I don't see why Batman has to know any sort of kung fu or wushu discipline when it isn't something he needs on a daily (or nightly) basis. Why does Captain America need to be a master of every form of fighting when the majority of what he does is throw a shield, throw some punches and kicks and uses wrestling and submission techniques?
Many of these characters would be absolutely fine knowing a few martial arts and incorporating them in an MMA style regimen (taking what works and disregarding the rest to form their own 'style'). I'm not saying all of them suddenly need to fight like that in the comics. I understand there needs to be an element of flair for things to look visually interesting, but often times the number of styles a person knows is often overstated instead of their tactics and how effective what they know is.
If anything, I think the recent live action versions of these characters have for the most part captured how these guys would fight as realistically as possible. And most of the time the actors are trained in only a few martial arts over and over again. There's a guy on YouTube that goes by GodzillaRex that usually breaks down the fighting styles from the movies and TV shows in question and the average number is usually 5 - 12. He does get some things wrong (and sometimes wrongly attributes a technique where it doesn't belong), but for the most part it makes sense.
T'Challa is actually a very good example of what I'm talking about, because he has formed his own fighting styles twice in the comics. First to combat the Doombots adaptive capabilities and another called Shadow Combat (being a blend of K'un K'un, Wakandan and Jeet Kune Do (Bruce Lee's fighting system)). The guy has made reference to Lee twice, and one of his philosophies in martial arts was to take what was useful from various disciplines and discard the rest. He even once said (to paraphrase) practicing one kick a thousand times is better than knowing a thousand different kicks. That's one of the things MMA is based on and the concept has been used in militaries for centuries.
T'Challa is one of the smartest people in his universe and one of the most experienced fighters. He of all people would understand the value of quality over quantity in martial arts. In his case I don't see why either he or Wakanda couldn't have developed a hybrid martial arts system that includes everything he needs to be a complete fighter: the best and most useful striking techniques (including claw strikes), grappling and throws, clinches and submissions, acrobatics, and various weapons training including disarming techniques.
All of that could be one martial art, T'Challa just needs to be a master of that alone, and coupled with his enhanced physicals, experience and intelligence he could be one of the best fighters in the world.