If a casual moviegoer were to ask an avid Marvel fan who the worst villain of the MCU is, more than likely they would automatically respond with Thanos. The MCU's big badThanos, quickly turned into quite the villain who left their mark on the MCU.

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However, while Thanos has had many villainous moments over his MCU appearances, there have also been some moments where Thanos shows mercy and even compassion. The moments of mercy are what make Thanos such a fascinating villain. As such, here are five times Thanos was a monster, and five times he showed mercy.

Monster: Destroyed Knowhere

Given that Thanos is known for massacring half of just about every world he visits, it shouldn't be too big of a surprise that when he arrived don Knowhere, he utterly destroyed it and possibly the Collector, although audiences are unaware of this at first.

When the Guardians arrive on Knowhere in search of the reality stone, all appears well. Then Thanos reveals it all to be an illusion, stripping it back to show the once proud station in ruins, showcasing his evil and malicious nature.

Mercy: Took The Time Stone In Place Of Tony's Life

Sometimes, when a villain is the closest to achieving their goal, is when they're the most merciful. In order to get the time stone, Thanos engages Iron Man and other heroes in a battle that ends with Tony being impaled by his own armor.

Seeing that if Tony dies the one timeline that could stop Thanos would cease to exist, Strange gives up the stone, and, instead of killing Tony, Thanos leaves, showcasing one of his few gestures of mercy and kindness that one wouldn't expect from the Mad Titan.

Monster: Rewound Time And Killed Vision

There are many moments in films when the filmmakers fake out the audiences. Usually, these are moments when the moviegoers assume that danger has passed, only for the danger to erupt back on the screen in a bold and shocking fashion.

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In the final act of Infinity War, the Russo Brothers pulled the biggest fake-out by making it appear that Vision died, robbing Thanos of the mind stone. However, Thanos simply reverses time and kills Vision a second time, his monstrous side on full display for the shocked masses.

Mercy: Adopted Gamora As A Child

Everyone says it's the little things that make a difference and this even applies to villains. It's the small things, the tiny acts of mercy that can blossom and grow into larger acts of kindness, even if they are a little messed up or disturbing.

When Gamora was a daughter, her planet was attacked by Thanos and half of her people were killed. However, Thanos spared Gamora and raised her as his own, making for a surprising moment of messed up yet interesting mercy from the worst father ever.

Monster: Obliterated Avengers Compound

In the aftermath of Avengers: Infinity War, fans were awaiting the moment when the Avengers would undo Thanos' wrath and bring back everyone who they'd lost. In the end, they did succeed, bringing back the half they lost.

However... just when everything seems as though it's been righted, the 2014 version of Thanos arrives, blowing away the compound in an act of pure evil and violence, ruining an otherwise beautiful and serene moment.

Mercy: Spared The Hulk After Their First Battle

When audiences first see Thanos, immediately, they're meant to dislike him, standing among the bodies of Asgardians, torturing Thor with the power stone, and killing both Heimdal and Loki, fan favorites. However, many seem to overlook one small fact.

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Thanos is attacked by Hulk on the ship and after brutally beating him down, he actually has a moment where he spares Hulk, instead of killing him. It's a brief yet interesting moment where Thanos could have easily gone finished Hulk before Heimdall sent Bruce away but instead focused on Thor.

Monster: Tortured Thor

Whoever created the rule book for super-villains is probably making a killing as most villains tend to utilize the same brutal tactics as one another. Thanos is one such villain who seems to own a copy, tacking tactics that many villains follow and utilizing them.

On one occasion, Thanos uses torture as a means to get what he wants, using the power stone to painfully hurt and scar Thor in order to get Loki to give up the space stone. Such brutal action is something that stays with many moviegoers.

Mercy: Didn't Kill The Guardians On Knowhere

Even though Thanos is an egotistical maniac with plans of destroying half the universe, that is always his end goal, with the death of others not entirely on his agenda. While he'll kill as means of leverage or making a point, he never kills if he doesn't have to.

After getting what he wants from the Guardians of the Galaxy, Gamora, and the location of the soul stone, Thanos leaves the remaining Guardians behind instead of murdering them where they stand, a show of "good faith" in the titan's eyes.

Monster: Killed Half The Universe

It's truly a rare moment for the villain to actually win or achieve his ultimate goals in a film. Most of the time, the heroes win the day and manage to push the villain back but from the get-go, Avengers: Infinity War, always had a different feel to it.

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When Thanos snaps his fingers with all six stones and wipes out half the MCU, the difference really hit home. It was such a horrific act that fans literally cheered when Thanos met his demise not once, but twice in Endgame.

Mercy: Left Half The Universe

Despite his horrific actions, there is reason to believe and even speculate that Thanos wiping out only half the universe was an act of mercy. Given the power of the gauntlet, Thanos could have easily wiped out the entire world but instead strove for only half.

In Avengers: Endgame, five years later, the world seems to be recovering from the snap, with people moving on while mourning their losses and the universe seemingly repairing itself, making one wonder if it was all for the greater good and merciful act.

NEXT: Avengers Endgame: 5 Reasons It Was The Perfect End To The Infinity Saga (& 5 It Wasn't)