Marvel has presented a variety of heroes to readers over the years. A great thing about them is how different they all are. While there are many archetypes that are the same, each of them fits into it in different ways. They are defined by a variety of things, but chief among those is courage. Courage is something that every superhero has in common, but some go further than others.
For some Marvel heroes like Captain America or Daredevil, courage is their defining characteristic. Their entire heroic career is based on their courage. They are an example to everyone else who fights alongside them, courageous and inspiring their fellow heroes to overcome their fears and hesitations.
10 Black Widow
Some Marvel heroes have hidden reserves of strength, which has always described Black Widow. Natasha Romanov joined the Soviet spy services after graduating from the Red Room and was a premiere intel agent for the USSR. She'd eventually defect, working with heroes like Daredevil before joining the Champions and later the Avengers.
Black Widow's courage prompted her to fight for her homeland, and it took just as much to defect. Since then, Natasha has always thrown herself into every fight, fighting the most dangerous foes and never batting an eye. She may not be the strongest person on the battlefield, but she always makes an impact.
9 Nightcrawler
Nightcrawler has the looks of a demon, but the heart of a swashbuckler. Courage has always been a big part of who Nightcrawler is, down to his mutant power. Teleportation is fraught with peril even under perfect conditions, and battle is anything but perfect. However, Nightcrawler will jaunt around the battlefield like it's nothing if it will save a life.
Nightcrawler is a hero through and through, his courage carrying him through every situation. He's always on the front line of every battle, ready to give his all. His faith is a part of his courage, as he believes that the divine will get him through any situation and that if he dies, he died fulfilling his purpose.
8 Wolverine
Wolverine is short in stature but tall in courage. He's the type of hero who will throw himself in front of the Hulk to protect his friends. There's no such thing as odds when Wolverine is around; he's jumping in to fight anyone he sees as a threat. He threw himself at Thanos when the Mad Titan had the Infinity Gauntlet. Wolverine's reserves of courage are legendary.
His healing factor and adamantium skeleton allow him to survive anything, but his courage is what keeps him going in every situation. Wolverine gets scared, but he's long since defeated that part of him. He'd rather die than his have his friends – or any innocent person – suffer, and there's nothing that will keep him from the fight.
7 Black Panther
Black Panther has a venerable legacy, with the forebears of T'Challa passing the mantle down through their family. As king of Wakanda, courage is a must. The most powerful people in the world want what Wakanda has, and Black Panther has to fend them off. He finds himself in the deep end constantly and has to fight his way through often overwhelming odds to win.
Fearlessness is in T'Challa's blood. Many have tried to cow the current Black Panther and many have paid dearly for it. His courage is part of why he's such a great leader. T'Challa wouldn't order someone to do something he wouldn't.
6 Captain Marvel
Carol Danvers's superhero history is a long one, and she's more than earned the mantle of Captain Marvel. Carol's road to being a hero began long ago, when she joined the Air Force. She worked her way up through the ranks and was the military attaché to Mar-Vell. Working with him awakened her Kree heritage, and she gained superpowers.
Since then, courage has defined Carol. She became a stalwart Avenger and even after she lost her powers, she still stayed around her heroic friends, trying to make a difference. She was able to beat her own demons, including alcoholism, to become a top class hero.
5 Thor
The Avengers are known for tenacity, especially Thor. For millennia, the Odinson has fought wars against the enemies of humankind and Asgard. While he was known for his arrogance and foolhardy attitudes, no one could doubt his courage. Since coming to Earth, he's learned humility but one thing that hasn't changed is his courage.
Some may think that a god's courage mean nothing because of their power, but Thor always throws himself into the fray against beings that outclass even him. He keeps fighting no matter what, putting his life on the line for Midgard.
4 Iron Man
Iron Man is a great hero, but a complicated man. Iron Man has done some things that have made some heroes question him, however his courage has never been in question. The best example of this comes from the beginning of his time as Iron Man. Tony Stark was injured, with a piece of shrapnel in his chest. Any other pampered rich kid would have done what he was told and built weapons for his captors.
Tony, instead, worked with Yinsen and created a suit of armor that would allow him to escape. He risked his life for his freedom and then continued risking his life for others. There are many bad things that can be said about Stark, but his courage in unfathomable.
3 Daredevil
Daredevil is known as the "Man Without Fear." Rendered blind by radioactive waste, his other senses were enhanced and grew to take the place of his lost sight. Matt Murdock decided that he would live a life of service to justice, both as an attorney and as the superhero known as Daredevil.
Every night, he put on his costume and threw himself into battle against the greatest criminals in New York City. By day, he fought them in the court of law. Everything he did risked his life, and yet he never gave up. In fact, the worse things get, the harder he fights.
2 Hawkeye
Clint Barton has gone by many superheroic names, but the one that made him famous is Hawkeye. Courage and Hawkeye have long gone together. His first fight in the superhero world was against Iron Man, and he was merely armed with a bow and arrow. He next joined the Avengers and became an institution on the team, always ready to take on all comers.
Hawkeye is a human being without superpowers - except for that short time he used Pym Particles - who fights the greatest threats the universe can throw at him with a bow and arrow. He could die from even a glancing blow from many Avengers' enemies, and yet nothing can stop him from being in the thick of battle.
1 Captain America
Captain America is an inspiration, and his courage is a massive part of that. Steve Rogers was the proverbial ninety-eight pound weakling, but he had a heart like no other. He wanted to fight the Nazis no matter what and volunteered to become a supersoldier in order to do battle with the greatest enemies of freedom. He became Captain America and took the war to the Nazis.
After being reawakened in modern times, he rejoined the fight again. The world was full of ultra-powerful new foes; Cap only has his shield and his muscles. None of that mattered to him, though. Steve kept fighting the good fight, no matter what the odds.