Natasha Romanoff is an Avenger who has one of the most complicated histories. After being turned into a killing machine while in the Red Room, Romanoff took the name Black Widow and became an effective hired gun. She would travel the world for her various assignments, seeking the best way to eliminate her targets. Because of this, she left a big trail of bodies before she joined the Avengers. Even after she became a fully fledged superhero, she still caused a few deaths as well, whether it be to save a friend or because she didn't feel that she had any other choice.

RELATED: The 15 Most Satisfying Punisher Kills

Because she crossed the threshold of taking someone's life in the past, she's not afraid to do it when necessary. Since her inception, Black Widow has killed a lot of folks, but some of her kills have been noticeably more vicious than others. Regardless if they were bad or good guys, the main theme is that they crossed the Black Widow and paid for it with their lives. She's not an Avenger that should be messed with. With that out of the way, let's take a look at 15 of the most vicious kills made by the Black Widow.

15 WHEN SHE KILLED HER OWN BROTHER

Vindiktor Romanoff

Part of the reason Black Widow became such an effective killer was that she had a tortured past to send her down that road. When she was little, she lived with a seemingly happy family. One fateful day, their house caught fire, and their mother managed to get all of the children out. However, Natasha was forced to fend for herself, as her brother Vindiktor abandoned them.

Eventually, she went back to Russia, where she went face to face with her brother once more. Needless to say, she was furious with him for having left her. He responded by trying to kill her, but her experience was greater than his. She got the upper hand on him and ended his life. No doubt this event took a toll on her psyche.

14 WHEN SHE SHOT JARVIS IN THE HEAD

black widow kills jarvis

The Ultimates comic series has some interesting changes to Marvel's continuity, love it or hate it. Among them was the relationship that blossomed between Tony Stark and Natasha Romanoff (keep in mind this is a different universe than the main one). As they progressed in getting to know each other, Stark's butler, Edwin Jarvis, wasn't very trusting of Romanoff.

Jarvis and Romanoff remained at odds for quite some time, until one day, she shot him in the head. Apparently, there was a traitor in the midst of the Marvel heroes, and it was Romanoff the entire time. After killing Jarvis, she revealed herself and left the team. This event had a lasting impact on Stark, who nearly broke down at the loss of his butler in Ultimate Comics Ultimates #1.

13 WHEN SHE SLAUGHTERED JASPER SITWELL 

jasper_sitwell

Jasper Sitwell was one of the top agents in SHIELD. He graduated at the top of his class in the academy and took the job of Nick Fury's personal assistant. He had later been involved with Stark Industries as a guard and continuously operated wherever SHIELD was needed. Unfortunately, when working for such a prestigious organization, you're always in the road of danger.

After the Winter Soldier began running around, Jasper and Nick Fury worked together to try and find him. This led them face-to-face with a brainwashed Natasha Romanoff. Without proper control over her actions, she fought the two SHIELD agents and shot Sitwell, killing him on the spot. As if that wasn't interesting enough, Sitwell later returned from the dead as a zombie.

12 WHEN SHE MARRIED SPIDER-MAN (WELL, NOT REALLY)

spider-man-black-widow

The What-If? stories are always intriguing. It's a fun way of exploring possible alternatives without it having any impact on the main continuity. One of these comics involves the Black Widow and Spider-Man getting hitched in What-If? #34. Get ready, because this one is a doozy, but thank God it's not a particularly long story.

It shows the marriage of Peter Parker and Natasha Romanoff, whose superhero names pair them up perfectly. However, it's not long before Black Widow actually eats Parker, with a shot of his tattered suit on the ground. This is a nice nod to reality, where the female Black Widow spiders actually devour their mates. It's a cute story, but it's a disturbing one nonetheless that makes us question the sanity of the real Natasha Romanoff.

11 WHEN SHE SHOT JEAN GREY...

black widow kills jean grey

Jean Grey is one of those characters that is known for dying. Ever since "The Dark Phoenix Saga" put her at the business end of Wolverine's claws, it's only a matter of time before she bites the dust again. There came a time in Secret Invasion where she also killed by Black Widow, but it's not for the reason you might think at first.

In this arc, the Skrulls had come to Earth and taken the identity of many heroes. Because the aliens were fighting the Marvel heroes, everyone was on edge. It came time for Black Widow to come face-to-face with Jean Grey, and because she didn't believe her to be the real one, shot her dead. As it turns out, the Jean Grey that was killed was actually a Skrull, so no real damage was done to the bond between X-Men and Avengers.

10 ...AND THEN SHOT BEAST

black widow kills beast

Beast was another character who was put on the wrong side of Black Widow's guns during the Secret Invasion event. After becoming a mutant, Hank McCoy still kept his gentle and intelligent personality. He was a powerful hero and one of the most brilliant X-Men to have ever lived.

Because of this, it was a dead giveaway to Natasha when he and Jean Grey jumped on her and Iron Man. Instantly deducing that this version of Beast was a Skrull, she shot and killed him as well. While it's true that they were aliens in disguise, seeing the face of friends as you're trying to kill them is something that could've weighed heavily on anyone. However, with Black Widow holding the firearm, there was no hesitation whatsoever.

9 WHEN SHE BLEW A HOLE THROUGH IVAN PETROVICH

Ivan Petrovich black widow

Because of Black Widow's dark past, many wondered how she managed to survive so long. This was because of a man named Ivan Petrovich. He served as her guardian for many years and took her to the Red Room to become a Black Widow as a means of protecting her. As time went on, he eventually revealed that he had a romantic attraction to her, despite being much older.

After Romanoff didn't reciprocate the feelings, Ivan disappeared for quite some time. When he finally returned, he was a cyborg and was slowly going insane. While Natasha didn't want to accept it, her old friend wasn't himself. He even tried to bring nuclear devastation to Earth. This led the Black Widow to take charge and kill her old friend for the good of humanity.

8 WHEN SHE KILLED EVERYONE TO SAVE HAWKEYE

Andras Bertesy black widow

Black Widow has a duty to her country and planet, but has an even greater duty to those she deems her friends. One mission saw her going face to face with a dangerous man named Andras Bertesy. This man amassed his fortune on trading illegal weapons, selling humans to slavery, and shipping out drugs. As if that weren't bad enough, he also had a knack for the mystic arts which always spells trouble.

SHIELD retaliated against this man, but Hawkeye, one of Natasha's close friends, was captured in the process during Secret Avengers Vol 2 #1. In that instance, the mission was only about rescuing him. She infiltrated Bertesy's organization, slaughtered all of the guards, and killed the man where he stood. She then saved Hawkeye from certain doom, reassuring us that even this widow has a heart.

7 WHEN SHE HELPED DEVOUR GALACTUS 

black_widow_galactus

Before you start going crazy, understand that Galactus made this list on a technicality rather than being a target of Black Widow. The Galactus we're talking about in this case appeared in Marvel Zombies Vs Army of Darkness #5. If you're familiar with the Marvel Zombies series, you'll know that all of the great heroes have been turned into undead monsters. In this issue, Galactus comes to Earth with all of his might.

Despite these great powers, the Marvel Zombies are simply excited that there's another meal to be had. They all swarm the giant, and through their collective might, bring him down. Among them was a zombie Black Widow, who wasn't much different from a regular Black Widow save for some decaying flesh and an appetite for bodies and brains.

6 WHEN SHE HAD TO KILL HER BEST FRIEND

black widow marina

While the name Marina might not mean much, know that this was one of the most difficult kills for Natasha to make. When she was still in the Red Room, she gained a friendship with a girl named Marina. The two got into all sorts of trouble, but ended up being competent operatives for the organization. One mission saw them going to Cuba, where Marina went undercover by living with her new boyfriend.

However, rather than being detached from this life, Marina grew fond of her lover and their adorable cat. Because of this, the Red Room ordered Black Widow to kill her after the mission was done. Widow hesitated greatly, but ended up shooting the boyfriend before going into the home. She snuck up on Marina (whose back was turned), thought for a long while, then shot her friend from behind.

5 WHEN SHE KILLED THE PROPHET

black widow prophet

There are countless villains in comics who believe that their means justify the ends. The Prophet was the head of a group known as Chaos who wanted a brighter future for mankind by using their knowledge of the future to orchestrate powerful events across the world. It's not hard to imagine how an organization like this can become corrupt in no time.

Black Widow ended up trying to fight Chaos, but was discovered and captured by the Prophet. He tried to make her see things their way, but she proved to be defiant and refused to join. He then got her attacked and she was thrown into freezing water. However, she managed to climb out, sneak up behind the Prophet, and stab him in the throat. After that, she threw his body in the water, ensuring that he would die.

4 WHEN SHE ASSASSINATED A HUSBAND AND WIFE 

black widow comienza

When Black Widow and Marina were assigned to a mission in Cuba, it was there that Natasha pulled off yet another vicious kill. It was there that Fidel Castro felt that two of his agents, Jose and Jema Comineza, had information that they were willing to let seep to the U.S. It was then that he called on the Red Room to deal with these two folks.

Natasha went undercover as a businesswoman who consulted with the Comienzas. However, she wasn't going to kill them outright. She needed to make sure they had the information. After tricking them into letting it slip, she knew what she had to do. While they were driving to what they thought was their freedom, Widow was at a distance with a sniper rifle and gunned them down where they sat. At that point, the mission was accomplished.

3 WHEN SHE STABBED A TELEPATHIC MUTANT

black widow kills rose

There are many mutants in the Marvel Universe, but one such mutant woman named Rose was completely insane. She had telepathic powers, but her mother told her that she wasn't special because there were others like her. This led Rose down a war path to kill all of the other telepaths in the world. After gaining a killing spree of around 40, SHIELD called on Daredevil and Black Widow to handle her.

Rose proved to be a difficult combatant, with impressive fighting skills as well as her super abilities. Black Widow ended up snapping the neck of her partner before moving onto Rose. While the telepath had complete control over Natasha, Daredevil attacked her. This gave Black Widow the opportunity she needed to take a knife and thrust it into Rose's heart.

2 WHEN SHE SHOT AN ACCOUNTANT

black widow rashid

Rashid was an accountant in Pakistan who was helped by Black Widow in the past. The operation itself put her at odds with Hawkeye, who was trying to prevent Rashid's escape from the country. Later on, this aid meant nothing to her as he was in cahoots with Chaos and wanted to get to Black Widow by kidnapping one of her allies. He then worked fervently to try and kill her, but to no avail.

Rashid kept trying to get at Black Widow and even tried to kill her friend. After failing, he decided to leave the U.S., but was tailed by Natasha. She disguised herself as a member of Chaos and interrogated Rashid to get special information. After getting what she needed, she killed him on the spot, thus ending their game of cat and mouse.

1 WHEN SHE DROWNED A CYBORG ASSASSIN

black widow molot bolga

In many stories, we see a theme of people using their religion to justify their own extremes. That's exactly what happened with a monk who was excommunicated. He felt that his crazy actions of terror were what God wanted him to do, so, he quickly moved on to try and assassinate world leaders, but Black Widow was there to stop him.

The two engaged in battle until a plane nearly crashed on top of them. The turbine snagged Boga, and he was taken down, seemingly killed. However, he returned with a metal body to fight and kill Widow, but she was too clever for him. While he couldn't be harmed by bullets, they fought on a ship, and she threw him overboard. His excessive weight prevented him from swimming to safety, and he merely sank to the bottom where he inevitably drowned.

Are there any more Black Widow kills that we missed? Let us know in the comments section!