Let’s start off with Thanos’ most famous act of villainy — wiping out half of all life in the universe. He’s done it on a couple of occasions, starting with the comics where he did it to appease the embodiment of Death. Thanos was dead at the time, but Death resurrected him, seeing as there was an imbalance in the universe. She tasks Thanos with eliminating half of all life forms, and he’s more than happy to oblige.

Balance is also the name of the game when it comes to the MCU. However, this time, Thanos isn’t trying to win favor with Death, who would later be embodied by Aubrey Plaza in “Agatha All Along.” Instead, Thanos saw what overpopulation did to his home planet of Titan, and in a bid to prevent resources from dwindling throughout the cosmos, he wants to collect all six Infinity Stones to erase half of life. He’s successful by the end of “Avengers: Infinity War,” so even though Thanos wasn’t supposed to be the big bad of the MCU, he nonetheless made his mark.

Given his penchant for death and murder, it’s perhaps not surprising to hear Thanos is a bad dad. “Infinity War” shows how little he cares for those he supposedly loves the most, as he tortures Nebula (Karen Gillan) to get information about the whereabouts of the Soul Stone. Once he learns it’s on Vormir, he takes Gamora (Zoe Saldaña) with him, as he’ll need to sacrifice a loved one to acquire it. This results in him tossing Gamora off a cliff so that he can wield the power he’s sought for so long. 

Comic Thanos is somehow even more awful. In the “Thanos Rising” storyline from Jason Aaron and Simone Bianchi, we learn how Thanos had children with many different women when he was younger. However, Death rears her head later in life and tells him to prove how he would belong only to her. This leads to Thanos traveling from world to world, killing all of his children as well as their mothers. It turns out simply being a deadbeat dad would’ve been the preferable outcome in these scenarios. 

Don’t invite Thanos to a family reunion. In addition to killing legions of his own children, he also kills his mother in Marvel canon. To be fair, this isn’t entirely unwarranted, as his mother, Sui-San, tried to kill Thanos after giving birth to him. From the moment he was born, his mother knew he possessed the Deviant gene, which explains his ugly appearance that makes him stand out amongst other Eternals, including his much more handsome brother, Eros. Sui-San was only stopped in killing the baby by A’Lars, Thanos’ father, and seeing what Thanos would become, maybe he should’ve just let her get it over with. 

It can’t be understated how much Sui-San truly despised her son. In “Eternals” #10 from Kieron Gillen, Esad Ribiç, Darren Shan, and Matthew Wilson, Sui-San delivers this line to her child: “I do not believe in unconditional love, Thanos. But know this: My hate for you is unconditional.” The exact method by which Thanos kills his mother varies depending on the specific comic issue you’re reading. Once, he kills her during a full-scale blitz on Titan. In “Thanos Rising” #2, he kills and dissects Sui-San to gain a better understanding of his vile nature. 

“Thanos Annual” #1 contains several short tales showing off new sides to the Mad Titan. One of these is “What to Get from the Man Who Takes Everything,” from writer Christopher Hastings and artist Flaviano Armentaro, where Thanos visits an ordinary guy named David every year on his birthday to torment him and ruin his life in some new way. This includes killing his father, getting his girlfriend to break up with him, and flooding his apartment. 

When he’s a child, David tries to warn his parents about the “monster” about to visit him, but no one believes him. Why would they? Thanos is known across the cosmos as an omnicidal maniac. Why would he waste his time messing with some guy who isn’t even a superhero? There’s no rhyme or reason for anything Thanos does to David. He’s completely innocent, but it just goes to show the depths of Thanos’ depravity. He loves inflicting death and harm so much that he’ll choose one random human and make their life a living nightmare. 

In the MCU, Thanos proposes an idea to stunt accelerating overpopulation on Titan — kill half of the population. Naturally, the other residents of the planet reject such an idea and banish the genocidal maniac. As it turns out, only killing half of those on Titan is far preferable compared to what Thanos did in the comics.

The “Thanos Rising” storyline focuses on the supervillain’s origins, and in the last issue, he pays a visit to his home world after amassing a legion of followers and a heavy arsenal of nuclear weaponry. He lays siege to the planet, annihilating everything in his path before touching down on the planet personally to slaughter whoever remains. Titan remains a desolate wasteland for years after, with the only visitor being Thanos to walk amongst his destruction periodically. But the vile brute’s quest for death and blood wouldn’t end there, as he would soon set his sights on the remainder of the universe. 

Thanos’ cruelty knows no bounds. “Thanos” Vol. 2 #15 from Donny Cates and Geoff Shaw shows off a new version of the Mad Titan. There are plenty of sci-fi heroes who could handily beat Thanos, but Earth’s Mightiest Heroes in the Marvel Universe were no match this time around for King Thanos.

The arc sees the present-day Thanos travel to the future, where he meets King Thanos, a future version of himself who successfully kills virtually every superhero. One of the few who remains is the Hulk, probably because he’s too difficult to kill, but he receives a fate far worse than death. Thanos keeps the big guy locked up in a dungeon, with his only food source being his fellow fallen heroes. Steve Rogers apparently screamed bloody murder while being consumed, suggesting that the heroes are being fed to the Hulk alive. And if you look carefully in the panel, you can see skeletal remains for Wolverine and Thor. It’s no wonder the only words the Hulk manages to get out are, “Kill… Hulk?”

With so many storylines involving Thanos over the decades, it’s no surprise to see him racking up wins every once in a while. He’s even managed to kill various superheroes, and regardless of whether the hero stayed dead for a while or came back, it doesn’t make the panels any less shocking.

The “Infinity Gauntlet” arc is one of the most well-known Thanos stories, and Issue #4 from Jim Starlin, George Pérez, and Ron Lim sees him kill many heroes, including Captain America, Spider-Man, and Iron Man. He even traps Cyclops’ head in a see-through cube, cutting off his oxygen and slowly suffocating him.

“Civil War II” from Brian Michael Bendis and David Marquez begins with the Avengers ambushing Thanos, who punches a hole clear through War Machine’s chest. And “Thanos” Vol. 2 #10 from Jeff Lemire and Germán Peralta sees him clap down on Sam Wilson’s head, with the only sound emanating from his crushing skull being “Splort.” Thanos is one of the most feared beings in the universe for good reason. He’s actually successful in killing large swaths of people at a time, so you need to watch out before getting into a fight with him.

Marvel Comics kicked off the 2000s with a new line of stories set in the “Ultimate” universe, set on Earth-1610 rather than the mainline Earth-616. In this universe, Thanos is the draconian dictator of his own empire, making him bear a strong resemblance to the DC character, Darkseid, who could’ve been a Marvel character in a different timeline. And instead of collecting Infinity Stones, this Thanos variant wants to get his hands on the Cosmic Cube.

He possessed it millennia ago and used it to bend entire populations to his whim. This included killing off large groups of people all at once or even keeping some in stasis, where they’re still conscious of what’s happening but are unable to move. Fortunately, the Cosmic Cube gets destroyed, but Thanos is nothing if not determined to get what he wants. That’s when he turns to Reed Richards of the Fantastic Four to make him a new Cube. If there’s one constant across the multiverse, it’s that Thanos is always on the hunt for various knick-knacks and doodads.

Many have died at Thanos’ hands over the years. Most of the time, they’re trying to prevent Thanos from exterminating a planet, but when it comes to the Ovin Mercenaries, they were just kind of minding their own business. 

“Cosmic Powers” #1 from Ron Marz, Ron Lim, and Jimmy Palmiotti opens with Thanos overlooking a slaughtered army. Only one being remains, and Thanos makes quick work of them. There’s no context of the beginning of what exactly transpired, so it makes sense one might assume Thanos came to conquer this planet or something. But then we learn the truth — Thanos was bored. 

One of Thanos’ robotic servants asks if the army proved a worthwhile “diversion,” which seems like an insulting term for those as feared and powerful as the Ovin Mercenaries. But Thanos makes clear that they weren’t even fun for him to defeat: “They were as cattle led dumbly to the slaughter… And proved hardly worth my effort. It’s one thing to be killed by Thanos after a glorious battle to protect loved ones. But in this case, numerous beings died because Thanos had a free afternoon he needed to fill. 

The Avengers frequently leave Earth to deal with intergalactic threats on other worlds, but it would probably be useful to leave at least some strong heroes on the home world just in case. The “Infinity” arc sees Thanos ultimately achieve his goal of conquering Earth, and part of that involves blowing up Wakanda. 

Thanos, along with the Black Order, annihilate Wakanda from the sky after Namor tells them that’s where the Infinity Gems are located. Many within Wakanda’s army are left for dead, and to add insult to injury, Thanos wasn’t even present during its destruction. He saw Wakanda as inconsequential enough to have his underlings do the dirty work, but it’s a horrific sight nonetheless. 

The “Infinity” arc began in 2013, and it definitely appears to be a strong influence on the climax to “Avengers: Infinity War” when the superheroes battle alongside the Wakandans against Thanos’ army in the same setting. Coincidentally enough, the reason the army arrives in Wakanda is also due to an Infinity Stone, namely the Mind Stone located in Vision’s (Paul Bettany) head.

On the surface, Thanos making Deadpool immortal sounds like a good thing, and it may objectively be the best thing Thanos has ever done, which isn’t exactly saying much. However, his reasoning for making Deadpool immortal proves his every bit of a psychopath as ever before.

It’s common knowledge by now that Thanos has the hots for Death, but Death doesn’t always like him back. In fact, there’s one storyline in the “Deadpool” comics where Death actually has a crush on the Merc with the Mouth. It’s a reciprocated feeling with Deadpool liking Death, too. Upon learning this, Thanos assumes the role of most jealous stalker ever by cursing Deadpool with never being able to die so that he and Death are forever separated. Deadpool has done his share of terrible things, too, but at least he’s funny about it. Thanos is simply depraved. 

As previously mentioned, Thanos’ father, A’Lars, aka Mentor, saved his life as a newborn baby. Unfortunately, saving Thanos’ life doesn’t mean much to the Mad Titan, and it certainly doesn’t exempt one from mercy. 

“Thanos” Vol. 2 #2 from Jeff Lemire and Mike Deodato Jr. sees Thanos come down with a mysterious illness. He turns to his father for help developing a cure, seeing as Mentor possesses a genius-level intellect. But really, how smart can he be if he didn’t realize everyone would be better off if Thanos died as a baby?

Mentor’s unable to come up with a cure, and in a fit of rage, Thanos punches directly through his father’s chest. But right before Thanos’ attack, Mentor makes it known that he wished he had smothered Thanos as a baby and that his only regret is that he won’t get to watch Thanos die personally. And you thought you had messy family drama… 

An early sign of serial killers is how they often kill small animals in childhood before moving onto human victims. Thanos is no different, as he’s effectively a serial killer on an intergalactic scale and got started on his journey to universal annihilation at a young age. 

“Thanos Rising” depicts his origin, which began in earnest when he was a teenager, and he and some friends check out a cave that collapses on them. He finds his friends devoured by lizards days later, and he goes back to kill the lizards as revenge. But this also kicks off his fascination with death, and he soon moves onto Titanians to study. He abducts, kills, and dissects two lovers who were minding their own business in an attempt to understand his own twisted nature. The second issue of the storyline even contains this cold passage: “Among the Eternals of Titan, who had known peace for eons, it was said there did not even exist the concept of murder. Until the one called Thanos invented it.” 

“Thanos Rising” shows Thanos killing all of his children, but at least one managed to evade his wrath. Naturally, this is something a perfectionist like Thanos can’t let slide, so he demands his Black Order to go planet to planet in search of “tributes,” meaning all of a given planet’s young males. It’s a scorched earth attempt to ensure his lost son doesn’t eventually threaten his quest for power even though (surprise) it doesn’t work out for Thanos in the end. 

Thanos must’ve killed thousands, if not millions, of young men just to make sure his son never threatened him, and the only funny thing about this situation is that the Mad Titan still failed. It turns out the son he was looking for was half-Titan, half-Inhuman, and goes by the name Thane. The character actually plays an instrumental role in defeating Thanos and the Black Order at the end of the “Infinity” arc.

What’s worse than one Thanos? How about a whole army of Thanos clones infused with the powers of some of the most powerful entities in the universe?

The “Infinity Abyss” storyline from Jim Starlin and Al Milgrom reveals how Thanos has been creating clones of himself for centuries. But these aren’t any old Thanosi (the term for multiple versions of Thanos), as he would give them some of his foes’ abilities, like Professor X and Galactus. This was done so that he could better study their powers and figure out new ways to defeat them. 

Somehow, these clones are even more into the idea of death and destruction than Thanos Prime, and when they’re accidentally released, they set out to end all life. To his credit, Thanos teams up with a few superheroes, including Spider-Man, Adam Warlock, and Doctor Strange, to get the Thanosi under control. He may have done good in the end, but it was only to clean up a mess he created in the first place. Thanos can’t even do something good without there being a massive asterisk next to it.