Even my villains are rarely deplorable. As a matter of fact, most people dislike my protagonists more than my antagonists. I try to create antagonists that you can sympathize for while often having arrogant and/or prideful protagonists that I just enjoy playing. That said, it is once in a blue moon that I have a character that you can truly just despise, but there are two of them from an old and still running roleplay of mine that I did try to put on the Guild, but it never took off here. Each one did something in the plot that literally caused people to leave the roleplay and some claimed to break down, but each one had an entirely different feel to them in the sense of their roleplay style.
They come from a roleplay of mine called Chance and they were both some of the strongest (one the strongest for a solid three RP generations) of the roleplay, but in entirely different ways. Yue, the Whispering Wind and Vlaad, the Lightning King were their names, but they were somewhat reversed in the process by which they became so despicable. Vlaad actually died as one of the first arcs and was driven completely insane by a parasitic mutant named MacArthur. Yue, on the other hand, did not deteriorate as much as he grew more deplorable over time.
Chance, or Chronicles of Chance, is a Dystopian roleplay based around mutations to the human genome causing a variety of effects. There's actually a relationship between the strength of a mutation and the physical alterations it makes to a person called the Mutation Factor, but I won't go too deep into that. It's just important to note because I will be referring to the names of mutations, and I'll start with Yue.
Yue had only two mutations, both two of the rarest. First was the most advanced form of the Cannibalism mutation. Yue could eat the flesh of anything and take on its psychological and physiological traits. Second was the Magus mutation, which allowed him to access the energy around him and essentially perform the effects of any mutation with training. U'en, his father, and Uden, his grandfather, are the only other known people in a roleplay with countless characters made for it that have the Magus mutation, for comparison.
Anyway, Yue starts out abandoned by his father in a relatively tragic story. U'en is known as a Ley Master and makes it his personal mission to make the world a better place using the sheer power of the Magus mutation. U'en was the only character to ever manipulate time itself. A huge and rage-provoking plot element was that with preparation, U'en could revert to a moment just before meeting someone so that he always got a perfect first impression. Anyway, point being that U'en is basically the Superman of Chance. He spent years creating colonies far North of the rest of the world for mutants that were too mutated to reproduce or fit into normal society; some of them even hunted down and killed as 'monsters' or 'abominations.'
U'en ditched Yue and his mother. His mother was sick and her health was deteriorating due to an autoimmune issue. U'en nor any of the best healers or doctors could save her. I made it a very prominent thing in the roleplay that autoimmune disorders were literally the bane of everything; if your cells attacked themselves, you were fucked regardless of mutation. Point being, Yue grew up fatherless and isolated as he watched his mother die, but he wasn't helpless. He could wrestle and kill bears, was faster than galloping deer, could swim for extended periods of time, etc. He had taken on the traits of all the animals he had hunted and killed. In a way, Yue was partially feral. This was the entire setup until his mother died.
His mother told him to seek out his father. Long story short, Yue has very little idea how society works and takes disgust in the mannerisms of people. He had no qualms or remorse about killing those he found disgusting. Over time, Yue figured out how his cannibalism mutation worked and eventually began hunting down mutants to kill, eat and add their powers to his collection. Combined with the fact he could use his Magus mutation to essentially recreate any mutation, he became really broken really fast. He collected most of the common mutations and began hunting down the less common ones as 'game' with the belief that he would eventually find his father one day, thinking if his father had similar powers to his then he should eventually find him simply by seeking out power.
Yue becomes power hungry, sure, but he also becomes schizophrenic. He can feel the memories, temptations and sometimes even hear the thoughts of those he killed and ate. This slowly eats at his psyche. This is around when I introduced him to the plot. At this point, he's looking for some of the most powerful mutants alive, and in doing so becomes part of a band of mutants called The Deck which are rogue bounty hunters from the Bounty Hunter Guild. He seeks to kill the aces and absorb their powers instead of eating their flesh, hoping that he could deal with two or three loud voices better than hundreds of quieter ones. Long story short, that's not how this turns out.
This is actually where Yue's story crosses over with Vlaad's. Sami, the mother of Vlaad's last children, was pregnant with twins. Sami was a genetically modified mutant made from the DNA of several mutants, one notably being a powerful mutant named Nero. Point being, each child had immense potential. Not only that, the story of Sami was a tragic one. Sami was roleplayed out in a full class of like 8 IC students being trained to hunt down and kill S-class mutants. She had hundreds of posts of backstory to her. Basically, she became one of the leading protagonists in the story, even though her life was meant to kill. She actually has her children, but ultimately dies. One is named Opilius and goes on to be the husband of an S-class mutant named Lilith. The other child, the girl, had this huge plot centered around taking her to safety and making sure she didn't fall into the hands of the oppressive, overbearing government(s). A character of mine as well, Sigh of the Twin Dragons. was her step-father and lover of Sami. Sami had already died protecting the girl.
Yue killed Sigh. Yue was hunting down Sigh, but he was looking for the other Sigh (an inconsistency in the roleplay forced me to create two characters very similar with the same names). Instead, he found Sigh and this little ball of potential in the form of a baby girl. Yue went batshit. If you've ever watched Hunter x Hunter, Yue basically had the same sort've hard-on that Hisoka gets for Gon and Killua. Mind you these are all basically my characters, but I digress. Yue kills Sigh nearly-effortlessly. Sigh's main power is... power-nullification. Yue didn't need his powers. Yue beat the shit out of Sigh and killed him. It was actually this traumatic scene where Yue is just bashing in the face of Sigh until his nullification wears off. Then, when it does, he lifts the child up and into his hands with what is basically telekinesis. In this scene, he just drains the child of its life slowly. Its crying and grows quiet. Its skin turns pale. Its life leaves it. Yue even turns the body of the child into the Hilt for a living sword later.
Anyway, that scene was enough to cause quite a few people from the arcs with Sami to leave, although ironically the roleplayer who played Sami stayed. Yue ends up finding his father. U'en actually lets Yue absorb him, although he fakes a huge fight, so that U'en can absolve Yue of all the voices and influence of basically everything he ate in his lifetime, thus making Yue turn into U'en 2.0, 'cept quite a bit darker.
Then there's Vlaad. Vlaad has two mutations as well. Teleportation and Electrokinesis. A fucking OP combo to begin with. He could teleport up to 4 times in one second, changing his position as he did and could do so basically infinitely with a fairly good range. That alone is broken. When you add in the fact that he could control the impulses in the body via electrokinesis so finely that he could take over the bodies like 97% of all living beings in the roleplay, read their mind, react as fast as possible, all while being simultaneously capable of hurling balls of Lightning that had literally the power of.. Lightning. Vlaad was meant to be OP. He was the strongest character in the whole RP, and he was one that never once got an IC fight.
Vlaad was only so powerful due to being the first and only master of Awakening. Awakening is basically pushing normal mutations to a higher percent, as obviously it was low to begin with. In any case, Vlaad was introduced to the roleplay via two characters called Far and Near. Brothers that represented the Bounty Hunters Guild. One could see anywhere in the world at any time, in any building. The other could see the future and past of any character, and I made damn sure it happened. Far and Near actually go back to a time when the leading characters in the roleplay were the Four Horsemen, whom were four individuals with horse-like anthropomorphic traits that saved the world from the feral mutants in the South American continent. Vlaad was one of them. Two of them died in the process and Far and Near were basically just part of the band that set it up. They also assisted with the creation of the Bounty Hunter's Guild and still do, I believe, far before the oppressive governments, churches, slave trade, etc. came into play.
Back to the main point, the group of soldiers Sami was with were sent to hunt down Vlaad. Rumor was MacArthur, a mutant whose mutation was actually the status of being an intelligent, colonized parasitic creature, had infested Vlaad. He killed whoever his host was, so he always aimed for superior hosts. So, he made Vlaad, the strongest mother fucker in the world, his host. For years, Vlaad didn't know. He simply ran the Guild behind the scenes. Slowly, he did start to deteriorate. When he was introduced to the roleplay, I made him seem healthy. Fact was, he had dementia. He had been reliving the same few months over and over in his head. Far and Near knew it and knew they could do nothing, so they just played along. I took care of a grandfather with dementia, so I applied real-life knowledge and experience to make it terrifyingly realistic.
Sami's entire group tried to kill Vlaad and failed, except for Sami - the most junior member - whom was recon. She almost lied out of the situation by saying she was coming to warn Vlaad and was from the Guild, but mind-reading is a bitch. Vlaad becomes enraged and almost kills Sami, but flashbacks to a former lover of his stop him. I then go on to roleplay out months of RP time with Vlaad not only deteriorating, but associating Sami with his former lover. Scenes include rape, Vlaad heart-brokenly not understanding why Sami spurs him, Vlaad awakening to reveal his black-skinned centaur form. Any time she even tried to kill herself, Vlaad stopped her by taking over. Vlaad kept her prisoner there until he died, and then he only died because another girl, Rebecca, came looking for help from Vlaad because she needed help against Orion (Vlaad, Orion and Lilith, at the time, were the only known S-rank mutants). Rebecca fucks up, gets captured, almost gets raped too and ultimately is assisted by Sigh of the Twin Dragons in her escape. Sigh technically kills Vlaad using power nullification and the fact Vlaad was half useless, then kills MacArthur via nullifying his power without a host.
Anyway, those two characters are EASILY the most terrible I have ever played. They went darker than I ever intended to go, but oddly enough, more people liked it than scorned it.
Other Facts: Vlaad, at one point, had several disfigurations that he corrected via mastering Awakening. Another physical trait of his, however, was an immense libido, which was taken into play countless times and one of the reasons Vlaad still often had to work from behind-the-scenes. Secondly, Sami and Sigh had matching DNA; the main source of the DNA that made them was that of Nero of the Nine Dragons. Although there were plenty of fade-out scenes for insinuation, this would allude to some form of odd genetic incest. If not for their death, I would have NO clue how to address any offspring they might have had.