In a world full of turmoil like the the Marvel Cinematic Universe, saving the innocent often comes at a dire cost. Heroes like the Avengers, the Guardians of the Galaxy, or the Sorcerers of Kamar-Taj risk their own lives – and often sacrifice them – to make sure the people they are protecting don't have to.

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Considering the huge number of heroes in the MCU and all their moments of courage, it's hard to give value to one act of sacrifice over another. Still, some instances do stand out over others, illustrating the true meaning of heroism and the character of the individuals involved.

10 Pietro Maximoff Dies To Save Clint Barton

Pietro's death in the MCU

The MCU's version of Quicksilver hasn't managed to reach the same popularity and notoriety as his equivalent in the X-Men movies, but his brief appearance in Age of Ultron remains memorable. Even if he is first a villain, seeking to avenge the death of his parents, Pietro and his sister both switch allegiances once they realize Ultron's plan. That may not have been truly heroic, but his final sacrifice is. Seeing Clint Barton in trouble while being targeted by Ultron, Pietro intervenes. He is shot in Clint's stead, and his sacrifice leaves his sister Wanda grief-stricken and lost.

9 Wanda Maximoff Drops The Hex, Sacrificing Her Family

Vision disappearing during his heartfelt goodbye with Wanda at the end of WandaVision

One of the most powerful characters in the MCU, Wanda Maximoff is more than anything a woman who loses too much. She loses her parents, her brother, and – when Thanos attacks – she loses her the love of her life, Vision. It stands to reason that she'd become emotionally unstable. In her grief, she creates an enchantment that turns the town of Westview into an idyllic fantasy, with her own copy of Vision present, two children, and even a version of Pietro involved.

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When she first realizes what she has done, Wanda refuses to release her Hex. But in the end, she understands that her actions are wrong. In the finale of WandaVision, Wanda drops her enchantment, freeing the citizens of Westview. The problem may have only appeared because of her, but the fact remains that Wanda sacrifices her husband and her children, to fix what she had done wrong.

8 Loki Attacks Thanos For His Brother’s Sake

Infinity War Loki's death

Villain-turned-unlikely hero Loki is about as unlucky in life as Wanda is, if not more so. After years of being at odds with his brother Thor, the two finally make amends and defeat their evil sister Hela. Things don't work out after that, as their ship is attacked by Thanos. In the ensuing battle, the Asgardians who survived Hela's rampage are decimated.

In a last-ditch effort to help his brother, Loki attacks Thanos with a dagger. Thanos easily incapacitates Loki, then kills him. According to the series Loki, one version of the character – identified as Classic Loki – manages to escape the incident, casting an illusion more powerful than anything he'd done before. It's unclear why canon Loki didn't do this, but his sacrifice is still tragic and noteworthy.

7 Groot Sacrifices Himself To Save His Friends On The Dark Aster

We Are Groot scene

The Flora Colossus Groot has given fans of the MCU plenty of interesting and amusing moments, but also some heartbreaking ones. In the first Guardians of the Galaxy movie, Groot and his friends are stranded on Ronan's burning ship, the Dark Aster. Groot wraps them in a cocoon of branches to protect them, saying "We are Groot" to reassure them. When the ship crashes, he dies, but they don't. His sacrifice is somewhat softened by the fact that a form of Groot is brought back at the end of the movie, though director James Gunn has said that Baby Groot isn't the original one.

6 Iron Man Flies To Seeming Death So He Can Save New York

Tony going into portal

The first Avengers movie will remain memorable no matter how many releases Marvel has in the pipeline. It was the first time the original Avengers assembled against a common enemy, in this case, Loki and the Chitauri. But as it turns out, the worst threat doesn't come from Loki at all, but rather, the World Security Council. In a panic over the invasion, they order the launch of a nuclear missile. It's up to Iron Man to save the day. He flies the missile into the wormhole, fully aware that it's most likely a one-way trip. He survives, but it's a very close call, and it leaves him with PTSD he never truly overcomes.

5 Classic Loki Sacrifices Himself To Alioth

classic loki

Classic Loki may have survived Thanos, but he doesn't manage to escape the Time Variance Authority. Pruned and sent into the Void by the TVA, he later encounters two younger versions of himself who intend to bring down the real force behind the organization. To do that, though, they have to get past the entity Alioth.

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Classic Loki casts a powerful illusion of Asgard, drawing the monster's attention and giving Variant Loki and Sylvie the chance to enchant the creature. Alioth consumes him, but this is truly a heroic moment. He embraces his death and dies with a tearful smile as he accomplishes his glorious purpose.

4 Doctor Strange Places Himself And Dormammu In A Constant Loop Of Death

Doctor Strange vs Dormammu

Stephen Strange goes through quite a journey in his origin story. Originally a skeptical man of science, he becomes the Sorcerer Supreme after his mentor's death and ends up having to face the interdimensional entity Dormammu. Summoned by the rogue sorcerer Kaecilius, Dormammu seeks to bring the Dark Dimension to Earth.

Using the Eye of Agamotto – the amulet holding the Time Stone – Strange traps Dormammu in a time loop, offering the entity a simple bargain, to leave or be trapped there forever. Dormammu doesn't react well and kills Doctor Strange countless times before finally giving up. Doctor Strange eventually wins, but it's an ordeal that speaks volumes of his character and selflessness.

3 Wanda Is Forced To Kill Vision To Stop Thanos

Wanda Kills Vision

The incident in Westview isn't the first time Wanda has to sacrifice her own happiness. During the Battle of Wakanda, she finds herself forced to destroy the Mind Stone powering Vision, just so that Thanos can't get it. The strength required to kill her own lover is admirable. In the end, Wanda's pain is all for nothing, as Thanos rewinds time and kills Vision all over again, claiming the stone.

2 Natasha Romanov Exchanges Her Life For The Soul Stone

Natasha Romanoff/Black Widow dies in the MCU

The first female Avenger, Black Widow has a painful arc in the MCU. Originally an assassin for the Red Room, she joins SHIELD through Clint Barton. She becomes an Avenger and considers the team her family. She doesn't always make the best decisions, but she does try. After the Snap, Natasha becomes the official leader of the Avengers, monitoring their operations at a far greater scale. When the Avengers receive the chance to change things, she happily embraces it.

She and Clint make their way to Vormir to retrieve the Soul Stone, only to find out the true cost of the Stone is the sacrifice of a loved one. Both Avengers wish to sacrifice themselves, and they actually have a brief fight over it. But in the end, it is Natasha who throws herself off the cliff, allowing Clint to claim the Stone. Natasha's body is never retrieved. At the end of the movie, she is lost and barely acknowledged.

1 Iron Man Gives His Life To Defeat Thanos

Iron Man Snapping His fingers

The final confrontation between the assembled Avengers and Thanos ends with the Mad Titan still retrieving the Infinity Gauntlet. At the last moment, Iron Man intervenes and grabs the Infinity Stones using his nanotech. Even through the armor, the Stones visibly hurt Tony, but he manages to snap his fingers anyway, defeating Thanos and his armies.

The radiation kills him, and he dies surrounded by his friends and family. His sacrifice is made even sadder by the fact that, after everything that had happened, Tony finally had a family with Pepper and their daughter Morgan. He will always be remembered as Iron Man, the hero who defied all expectations, faced his worst nightmare, and won.

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