Life for superheroes would be boring if there was no one to fight against but luckily, the team in Teen Titans doesn't have that problem. A new primary antagonist has been introduced in each season of the animated show, aiming to defeat the titans or destroy the world. There have been a few great secondary antagonists too.
While it's natural to adore the heroes, some villains get lots of love too, depending on how they carry themselves. Others do nothing but remind fans that they are indeed baddies. And whether or not a villain is liked mostly depends on their personalities, views, and the general way in which they relate with other characters.
Madame Rouge
Rouge serves as the co-leader of the Brotherhood of Evil. She has an array of powers that include shapeshifting, elongation, and regeneration.
Thanks to her sadistic nature, it's impossible to adore Madame Rouge. She has delusions of grandeur and has no respect for anyone, including her colleagues. Her arrogance makes her make her own independent decisions which always end up being detrimental to her team. Her delusions stretch to her opinion about the Titans too. When they outnumber her during a fight, she still believes she can defeat them, something that causes her downfall. Rouge has a low opinion of children too, describing them as useless.
Trigon The Terrible
The inter-dimensional demon lord is keen on taking over the universe. He plans to use his daughter Raven as a means to a portal that will make him control Earth.
Trigon is undoubtedly one of the most villainous TV dads, He doesn't care about his daughter and even tries to kill her at one point. The villain's plans of world domination greatly inconvenience his allies, including Slade, but he never seems to care. His inability to relate well with others ultimately causes him to be sent back to the same portal he came from.
Brother Blood
The charismatic and boisterous Brother Blood is the principal of the H.I.V.E. Academy. He previously served as a mentor for the Teen Titans too.
Blood's obsession with Cyborg makes him a creepy character. He takes such a keen interest in Cyborg's life that he makes it his mission to be like him yet he is more powerful. And as a teacher in a villain school, he is controlling over his students. Among his bizarre moments is threatening to drown his students with flood water if they offend him.
Blackfire
One of the things that don't make sense about Blackfire is why she is so eager to make sure Starfire doesn't succeed. Nonetheless, she never relents in her pursuit of that goal.
Blackfire is deceitful and heartless. She doesn't mind framing her sister for crimes she has committed. Her weird sense of humor keeps hurting the feelings of other characters too. Moreover, she is full of herself, preferring to tell her own stories rather than listen to those of others.
Terra
Terra is first introduced as a well-intentioned hero who struggles to control her powers. After being manipulated by Slade, she starts working with him.
Terra has been frequently painted as naive and that's why Slade can puppeteer her so easily. She also jumps to conclusions, something that makes her fall out with Beast Boy, one of the strongest Teen Titans members and the only one who genuinely cared about her. Terra is normally confused too and has never been able to figure out where her true loyalties lie.
The Brain
Once a great scientist, The Brain was reduced to only his brain after a lab explosion, He now serves as the co-leader of the Brotherhood of Evil.
Thanks to his genius-level intellect, The Brain always plans out his moves well, and as such, he normally gets the better of the Titans. He has a conscience too as even when he has had the Titans cornered, he never ordered their deaths, instead choosing to keep them imprisoned.
Killer Moth
Killer Moth commands a large army of mutant moths. The Titans have themselves confessed that he is one of their most headache-inducing foes.
The main thing that stands out about Killer Moth is his parental love. He would do anything for his daughter, Kitten, including taking the whole city hostage just so she can get what she wants. He is a staunch animal lover too and always takes great care of his moths, making sure to feed them and provide them with a safe habitat.
Slade
Also known as Deathstroke the Terminator, Slade is the biggest villain in the series. Despite not having special powers, he has consistently managed to outfox the Titans.
Slade has managed to win over fans by how calm and composed he always is. Even though it's always sad whenever he gets to defeat the heroes, his methodology is admirable. He never shows up unless he has the advantage and is always wise enough to flee when he feels he might lose. And while he is a good fighter, he employs brains rather than brawn by tricking opponents into traps and manipulating others to do his bidding.
Jinx
Early in the series, Jinx leads the villainous group known as the H.I.V.E. Five. She later gets into a passionate relationship with Kid Flash.
Jinx is the only H.I.V.E. member who happens to be compassionate. Whenever her teammates have advocated for severe punishment, she has never ruled in favor of that. She is the most hardworking member of the group too and has come to label the rest as lazy. Jinx has a couple of other unique characteristics as well, such as her fly-running style where she always spreads her arms wide while running.
Red X
When Robin creates the Red X suit for undercover missions, an unknown thief steals it. He then assumes the identity and begins committing crimes.
As a villain, Red X isn't malevolent. He only commits crimes for fans and to piss Robin off. He is quite good at mockery and sarcasm too, always reminding Robin how much of a mistake he made by creating the suit and that he wears it better. Red X also champions the greater good and has been more than glad to assist the Teen Titans in missions where they were outnumbered. Even more impressive is that Red X is a dance battler, making sure to mix martial arts skills with dance moves during duels.