One of the most significant issues with the Marvel Cinematic Universe since its inception with Iron Man in 2008 is its inability to produce, layered, compelling, and excellent villains. The MCU in the later stages has had some great villains like Killmonger and Vulture. None though, compared to the Mad Titan himself, Thanos.

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Thanos' introduction into the MCU was something anticipated for years with mid and post-credit scenes. When he finally made his mark on the universe in Infinity War, he did not disappoint. He was a villain who brought stakes to the world as well as an evil presence that was massively memorable. One of his best features throughout his time in the MCU was his quotability, for which there were tons. Here, we look at ten of Thanos' most menacing quotes.

"WAIT."

Not exactly a quote that springs to mind when you think of either Thanos or the word menacing, but Thanos' "Wait," to Nebula is a threatening quote, if not a badass one.

In Endgame, when Thanos arrives on Earth to collect the stones, he sends Nebula to retrieve them. When Nebula asks what he will do, this is his response, and he sits. It both shows Thanos' authority and gives the audience a sense of the confidence Thanos has. Especially since we know a battle with our heroes is about to commence, the impending doom that does not phase Thanos, but is inspired by him.

"I IGNORED MY DESTINY ONCE. I CANNOT DO THAT AGAIN. EVEN FOR YOU."

Thanos acquires the Soul Stone in Infinity War

Thanos had a clear goal that he worked on and sought out for years and years, letting nothing stand in his way once it was confirmed to him that his goal was the right one. Perfect balance. Half a universe, so that it may prosper.

Nothing would stand in his way, and this was shown to the absolute extreme in Infinity War when Thanos sacrificed one of the only things he truly loved, his daughter Gamora. To get the Soul Ttone, Thanos had to sacrifice Gamora, and he says that he cannot ignore his destiny again, even for her. When he says this, fans know what is coming, and it is heartbreaking and evil.

"ALL THAT FOR A DROP OF BLOOD."

Thanos has immense power that is evident throughout the Infinity Saga. Both as an intellectual madman and as a being who is not to be taken lightly in a fight. He proves this once more in his battle with the heroes in Infinity War. 

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When Thanos arrives on Titan, a few of our beloved heroes are there to face him. After a couple of minutes of fighting, Iron Man has a slight upper hand, making Thanos bleed, prompting him to say, "All that for a drop of blood." A quote that is smooth in its confidence and menacing in the knowledge that Thanos is about to get up and make Iron Man seem like nothing to him, despite the heroes' hard-fought efforts.

"YOU SHOULD HAVE GONE FOR THE HEAD."

Thanos' most iconic quote, and the one that sunk the hearts of millions, comes at the end of Infinity War. It is and will continue to be remembered by millions as one of the MCU's very best: "You should have gone for the head!"

Menacing means the presence of danger, which is what the audience feels when this happens. It appeared as if Thor had done it. That Thor had saved half the universe. But, as soon as Thanos musters the effort to utter these words, the fans know what is coming, and with one snap, half the universe disappears.

"REALITY CAN BE WHATEVER I WANT."

Quill points his blaster at Gamora and Thanos in Avengers Infinity War

The power of the Infinity Stones is immeasurable. Each presents a different type of energy, possibly used to cause extreme chaos and make their wielders God-like. Thanos knows this.

After hunting down and wielding the Reality Stone, Thanos talks to Gamora. He tells her that "reality is often disappointing." Now though, to Thanos, "Reality can be whatever I want."  The power Thanos holds, with the intelligence he has, is menacing enough and this quote just solidified it.

"I WILL SHRED THIS UNIVERSE DOWN TO ITS LAST ATOM."

In Endgame, when Thor kills the original Thanos, and Thanos from 2014 comes into play in his search for the Infinity Stones, he realizes that his initial goal cannot be accomplished with those such as the Avengers around to rebel. So he decides he must aim bigger.

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Pre-battle, Thanos tells Thor, Iron Man, and Captain America that he knows what he needs to do, and that is to "Shred this universe down to its last atom." From there, he says how he plans to create a new, grateful universe in his vision. Fans know what Thanos is capable of, and the thought of him having a more twisted and ambitious goal is scary.

"WITH ALL SIX STONES I COULD SIMPLY SNAP MY FINGERS, AND THEY WOULD CEASE TO EXIST. I CALL THAT MERCY."

Thanos in the MCU

When Thanos arrives on Titan to confront our heroes, it is a great scene. His initial dialogue with Doctor Strange gives a brilliant insight into the character, his history, and the motivations for his goal. It also lets audiences know what he plans on doing.

"With all six stones, I could simply snap my fingers, and they [half the universe] would cease to exist." This is what Thanos claims is mercy. It is a scary insight into his psyche, and it induces fear in the audience, knowing how determined he is, and how close to all the Infinity Stones he is.

"WHAT I'M ABOUT TO DO TO YOUR STUBBORN, ANNOYING LITTLE PLANET. I'M GONNA ENJOY IT. VERY, VERY MUCH."

Thanos Avengers Endgame

Thanos' goal has always been one that he feels is for the greater good that does not discriminate. He continually says as much. But, when Thanos from 2014 comes to Earth and knows everything that has happened, and battles with our heroes, his opinion on staying neutral in his destruction changes.

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He tells Thor, Captain America, and Iron Man that he tries to avoid making his aim personal. But he ends up giving in and is unable to contain himself from being happy at the prospect of destroying them and their planet, especially since his new goal is to start the universe anew.

"FINE. I'LL DO IT MYSELF."

Josh Brolin as Thanos in Avengers: Age of Ultron Post-Credits Scene

Thanos' attempts to retrieve the Infinity Stones were not always done by himself. He had a lot of minions he sent out to aid him, but they all fell. After this happened time and time again, the Mad Titan was sick of it.

"Fine. I'll do it myself," is indicative of Thanos' impending arrival into the lives of the Avengers and our other heroes in his search for the Infinity Stones. The knowledge that this is what that quote means is what makes it menacing. The incoming arrival of Thanos is exciting in the sense of fans looking for a great villain, but dire for our heroes.

"DESTINY ARRIVES ALL THE SAME. AND IT'S HERE. OR SHOULD I SAY, I AM."

Avengers Infinity War Thanos Space Stone

What is more fear-inducing than the knowledge that Thanos is coming? His actual arrival. This comes in Infinity War when he confronts and kills half off the Asgardians.

"I know what it's like to lose. To feel so desperately that you're right, yet to fail nonetheless as lightning turns the legs to jelly. I ask you to what end? Dread it, run from it, destiny arrives all the same. And now, it's here. Or should I say, I am," is Thanos' opening quote of Infinity War. It shows him hitting the scene in a big way, referring to a destiny not just as having arrived, but of destiny being Thanos himself, with so much destruction and heartbreak set to come.

NEXT: Avengers: 10 Worst Things Thanos Has Done In The MCU