The Marvel Cinematic Universe officially kicked off with 2008’s Iron Man and in the intervening years, has grown to include 16 feature films, various shorts and a handful of television series. Of course, the heroes get all the good press, but anyone who knows comics understands that the villains make the heroes great. Without compelling villains to battle, heroes become less interesting and the stories suffer. The MCU has decades of material to draw from and since the beginning, the creators have given fans a parade of fantastic villains. But along the way, they’ve made some missteps. What makes for a good villain?

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In our minds, a good MCU villain doesn’t necessarily need to be 100% comic book accurate, but we do like the characters to pay some homage to the original material. Villains also need to be visually interesting, especially if they're costumed. We like our villains to have clear, sensible motivations and plans that make some sense. Finally, we want a memorable performance. When we’re done watching the villain, something should linger. We don’t expect Academy Award-worthy material, but good characters leave a bit of themselves with us. Therefore, here are eight villains we think the MCU got right, and seven we’d like to see improved upon.

15 GOT RIGHT: ULTRON (AVENGERS: AGE OF ULTRON)

Ultron

The first villain on our list is a classic Avengers bad guy. Though the film shifts Ultron’s “father” away from his comic book lineage through Hank Pym in favor of the much more MCU familiar Tony Stark, it keeps some of the father/son tension. At his core, Ultron is just trying to remake the world into the image of his father’s dream, however misguided his interpretation might be.

The CGI looks solid throughout the film, Ultron’s motivations are clear and James Spader gives a rich voice performance that is menacing and affecting. Ultron is a far more complete human being than some of the villains on this list. The movie’s final confrontation between Ultron and The Vision, who are essentially brothers, is chilling in all the best ways.

14 GOT WRONG: BARON ZEMO (CAPTAIN AMERICA: CIVIL WAR)

Zemo

A common theme among the MCU’s less successful villains is a muddled motivation for their actions. In Captain America: Civil War, Zemo’s motivation makes sense -- he’s seeking vengeance for the deaths of his family during the Battle of Sokovia -- but the ensuing master plan gets lost among the film’s noise.

This is not the fault of the actor portraying Zemo. Daniel Brühl is a fine actor. The movie just doesn’t give him enough to do, electing instead to let the plot fall into hero vs. hero cliches. What results is a waste of a class Marvel villain who should have had a much more impressive cinematic presence. In a perfect world, Zemo returns from his imprisonment and angles his sharp intellect toward a clearer plan. Just keep him away from the Adhesive X.

13 GOT RIGHT: COTTONMOUTH (LUKE CAGE)

Cottonmouth

None of the best villains think they’re villains -- they are all the good guys of their own stories. This is certainly true for Cornell Stokes, also known as Cottonmouth. Portrayed as a businessman with a dark streak, a mafioso without the mob, Cottonmouth is smart, complex, deadly and tragic. He plays piano while essentially worshipping a giant Notorious B.I.G. oil painting, a study in contrasts.

Though the character lacks any of the accoutrements of his comic book counterpart, his nickname was perfectly explained and enough of a callback to the original material to make comic book fans happy. Played by the super talented, Oscar-winning Mahershala Ali, Cottonmouth is a great example of a “regular” man becoming important in a world populated with people who have bulletproof skin and glowing fists.

12 GOT WRONG: THE MANDARIN (IRON MAN 3)

Mandarin

The Mandarin isn’t the Mandarin. But for most casual viewers, this fake Mandarin is the only Mandarin they know. Let us explain. Oscar-winner Ben Kingsley appears in Iron Man 3 as the Mandarin, the leader of the terrorist organization known as the Ten Rings. They want to bring the modern world crumbling all around them.

Tony Stark learns during the course of the film, however, that the Mandarin isn’t the leader of anything, and is, in fact, C-list actor Trevor Slattery pretending to be the Mandarin on behalf of the film’s real villain, Aldrich Killian. For most movie-goers, that’s the end of things and the film has wasted both the talents of a great actor and the name of a classic Iron Man villain. The existence of the actual Mandarin is revealed in Blu-ray extras, leaving open the possibility that a good portrayal of the ringed meanie could still happen.

11 GOT RIGHT: HYDRA (VARIOUS FILMS AND SHOWS)

Hydra

As the MCU’s primary Evil Empire antagonist, Hydra is depicted as having its grubby little fingers everywhere. They’ve infiltrated the government, they’ve infiltrated S.H.I.E.L.D., and they’ve been manipulating events behind the scenes for as long as there’s been an MCU. At its worst best, Hydra is portrayed as a massive yet quiet, clandestine organization with eyes and ears everywhere.

Anyone and anything can be Hydra. They have psychotic despots, mad scientists, shady businessmen, arms dealers and disgruntled freedom fighters within their ranks. The MCU has struggled when it tries to feature villains hellbent on world domination, but with Hydra, they’ve included enough variety, and given them enough time, to make for a satisfying slow burn. Through Hydra, we’ve also been able to enjoy some of the final performances of some really fine actors: Gary Shandling, Bill Paxton and Powers Boothe.

10 GOT WRONG: DIAMONDBACK (LUKE CAGE)

Copperhead

An excellent villain needs an excellent look. We understand that comic book costumes often don’t translate well into the real world of live action entertainment, so we would never ask for a man dressed up like a snake to appear in anything from the MCU, but the approach the creators of Luke Cage take toward Diamondback’s look is inexplicable. It looks like a misguided welder uniform with a fancy backpack.

Besides that, Diamondback’s role in the series feels completely unnecessary. True series meanie Mariah Dillard makes good use of Diamondback -- because she always makes lemonade out of lemons -- but besides that, he feels very superfluous. As far as his name is concerned, while we enjoy the connection to the comics’ Serpent Society, the name “Diamondback” doesn’t get a satisfying explanation in contrast to the real-world explanation for “Cottonmouth.”

9 GOT RIGHT: GRANT WARD/HIVE (AGENTS OF S.H.I.E.L.D.)

Grant Ward

The MCU is at its villainous best when it uses its bad guys to charm us. One of the best examples of the charming villain is S.H.I.E.L.D. turncoat Grant Ward. Ward was set-up for his heel turn early in life. The product of an abusive household and on the path of criminality and mischief, Ward was “rescued” from juvenile hall by S.H.I.E.L.D. agent and Hydra mole John Garrett in a fateful pairing that would eventually lead to Ward’s betrayal of his team. It’s a complete betrayal when it comes: professional, personal and potentially deadly.

Actor Brett Dalton gives a solid performance as he maneuvers his way through all of Ward’s various identities, from loyal S.H.I.E.L.D. agent to Hydra villain to, finally, the possessed and parasitic Hive. He’s been dead before, so we expect, like before, Ward will manage to shake it off going forward.

8 GOT WRONG: KAECILIUS (DOCTOR STRANGE)

Kaecilius

What does Kaecilius want? Yes, he wants to be reunited with his deceased wife and son, but to get there he needs to betray the Ancient One and cross multiple dimensions and consort with Dormammu and retrieve a scepter and...you get the idea. Dealing with ancient powers and blending dimensions can be exhausting.

Doctor Strange suffers from the presence of just too many people racing after too much stuff, and therefore we never get to really understand or appreciate the villains’ motivations. Everyone feels betrayed, everyone has been hurt, and frankly, everything could have been solved if they’d just sit down around a table together and talk things through. But by the end of the film, it’s hard to even remember what Kaecilius was even up to. We might leave appreciating Doctor Strange for its stunning visuals, but the film’s villain has very little staying power.

7 GOT RIGHT: THE KINGPIN (DAREDEVIL)

Kingpin

The best villains are usually portrayed as deep and conflicted. One of the best examples of this approach to villainy is the Kingpin from the Netflix Daredevil series. Vincent D’Onofrio’s Wilson Fisk is determined, damaged, sensitive and, when he needs to be, utterly ruthless. This is a Kingpin equally comfortable hobnobbing at a caviar dinner as he is punching someone. Though he prefers to use his connections, minions and steel will to get his way, D’Onofrio has the physical presence to remind us of Fisk’s tangible strength.

Though this list focuses on the current MCU films and shows, we’d like to offer an honorary shout-out to the late Michael Clarke Duncan, whose portrayal of the Kingpin in 2003’s Daredevil was one of, if not the, best things about that movie.

6 GOT WRONG: RONAN (GUARDIANS OF THE GALAXY)

Ronan

Many of the complaints we level against Kaecilius apply to Ronan the Accuser from Guardians of the Galaxy. He’s off looking for the film’s MacGuffin, for one reason or another and his plans are needlessly byzantine. Additionally, he’s visually uninspired, lacks any interesting abilities and actor Lee Pace is never given much to do.

Whereas most of Guardians of the Galaxy is gleefully bright and manic, Ronan is dour. This was a film that could have used a scene-chewing fire breather as its villain, and instead we got a gray downer with a hammer. Ronan isn’t the only subpar villain in Guardians of the Galaxy; Nebula is also uninteresting. But the good guys in the film are so much fun, it’s easy to overlook the movie’s faults.

5 GOT RIGHT: MARIAH DILLARD (LUKE CAGE)

Mariah Dillard

We do like a schemer, and one of the best on Earth is councilwoman Mariah Dillard from the Netflix series Luke Cage. Portrayed by the fantastic Alfre Woodard, Dillard justifies her criminality by telling herself, and the public, that she’s working for the good of Harlem.

Her iron will was born out of trauma, and her path was set the same day her cousin Cottonmouth began walking his path. Dillard maintained a successful, respectable public face, even as she manipulated events behind the scene. However, don’t let that cool exterior fool you because she also has a mean streak, as evidenced by her murder of her cousin. It’s one of the most brutal acts seen in the MCU -- vicious and personal.

4 GOT WRONG: THE CHITAURI (THE AVENGERS)

Chitauri

No lies: the giant space dragons are really cool looking. The rest of the Chitauri, though, are uninspired cannon fodder that exist purely as punching bags. Ostensibly Loki’s army, when the Chitauri pour into our galaxy, their numbers are scary, but they lack any leader or focus to implant in our film-going memories.

Every potential despot needs his or her field troops, so in that way, the Chitauri nicely fulfill their purpose. Our complaint is that, for all the screen time and lip service they're given, the Chitauri aren’t the threats they should be. Wars of attrition, which is what the Chitauri are threatening to wage, aren’t compelling on the screen. With so many good villains to borrow from the original comic book source material, pulling in the little known Chitauri from Marvel’s Ultimate Universe seems like a wasted opportunity.

3 GOT RIGHT: KILGRAVE (JESSICA JONES)

Purple Man

As one of the darkest villains in the entire MCU, David Tennant still manages to charm and impress. In Jessica Jones, Kilgrave oozes loathsomeness and narcissism, all at the same time as we see how his childhood has left him terrifically scarred. He is seemingly incapable of expressing the slightest bit of empathy for another human being, and engages in some of the most vile crimes imaginable and yet, he can love.

Or so it seems. We never really understand if he loves Jessica for real, or if his obsession is little more than the feelings a child has when there’s a toy he can’t ever own. The beauty of Tennant’s performance is than either interpretation is equally valid. The Purple Man’s power set was always potentially one of the most terrifying in all of comic books, shown here with dark, sadistic glee.

2 GOT WRONG: THE HAND (VARIOUS NETFLIX SHOWS)

The Hand

In Marvel Comics, the Hand is famously known for its swarming masses of killer ninjas. As drawn by some of the best artists in the business, wave after wave of ninja warriors busting through a house like an unrelenting flood is one comics’ greatest all-time visuals.

In the MCU’s Netflix shows, however, the Hand is relegated to the shadows and complete darkness. They disappointingly attack only a few at a time and not in droves that comic fans are accustomed to. While their leaders can sometimes be interesting or compelling, as an organization, the Hand is never portrayed as a truly frightening adversary. They are barely ever depicted as ninjas! Ninjas are cool. Lots of ninjas is cooler. Stop messing around, Marvel, and start that ninja pile.

1 GOT RIGHT: LOKI (THOR AND AVENGERS FILMS)

Loki

Finally, the creme-de-la-creme of MCU villains, Loki has become as popular and as important as the heroes themselves. Abandoned at birth and rescued by Odin, Loki was never destined for a smooth life. Whereas his adopted brother, Thor, possessed all the typical strength of an Asgardian, Loki’s powers developed elsewhere.

The beauty of Loki’s villainy rests with his charm. Like so many of the best bad guys, Loki is a fellow you want to hang out with. He’s capable of terrible things, like mass murder and world domination, but you get the impression that, underneath that sly grin and awesome horned hat, is a half-decent fellow. Tom Hiddleston’s performance sells it and explains why, while villains may come and go, there’s almost always room for Loki in any MCU film.

Which villains do you consider the MCU’s best and worst? Let us know in the comments!