In Ah! My Goddess, most of the antagonists are sympathetic or at least have believable motives. The Lord of Terror was one exception. It was nothing more than a glorified computer virus that wanted to destroy the universe and recreate it in its own image, with the second part only being revealed a few pages before the arc ended. It had no real personality beyond being a cackling Card-Carrying Villain. It's also notably the only antagonist that was Killed Off for Real.
Kazuo Kiriyama in Battle Royale. The only justification for his actions is that they add lots of kills to the storyline and give the real characters someone to fear. In the novel and manga versions, his complete lack of personality is due to brain damage and he is unable to comprehend ethics. "I forget things sometimes..." Interestingly, while the scene explaining his background is beautifully written, he gets no perspective after that. Fitting this trope, he could be replaced with a 'battle robot sent by the organization' and it would be the same story.
Exclusive to the Japanese version is Demon from 02, who comes into the plot with no explanation, and is so powerful that the heroes can only seal him away. He has absolutely no personality, and his contribution to the plot is only as an "obstacle." For all its faults, the dub vastly improved on him, thanks to a delightfully hammy performance by the late Bob Papenbrook.
Mephistomon from Digimon Tamers wanted to destroy the world for no particular reason. The closest thing to a motive we get for him is Omnimon stating he was spawned from an Apocalymon that also wanted to destroy the Earth, presumably for the same reason as the one in Adventure (if it wasn't the same one).
Bottom and Black Hole of the second and third Pretty Cure All Stars movie series. Bottom and Black Hole were practically the same villains - monstrous ancient evils seeking to obtain the MacGuffin of that movie by resurrecting previous Quirky Mini Boss Squad members and giving the girls a hard time so he could take over/destroy the world. They're also powerful enough to wipe out the collective teams (knocking them back into human form in the case of Black Hole) that they HAVE to use their movie-only Super Mode to defeat them. On the other hand, Fusion, the Big Bad from the first movie and New Stage, seems to have a bit more personality, isn't seeking any sort of MacGuffin, fights the girls on his own and just wants to unite the world as a Hive Mind.
Of all the villains in Saint Seiya, Hades is perhaps the least motivated and most small minded. His grand plan is to cause The Great Eclipse, which will perpetually block out the sun and kill everyone on Earth. Being the king of the dead, you'd imagine he wants to do this because he wants an army of the dead to attack Olympus with, or maybe he's trying to give humanity a "peaceful" death because he foresees World War Three. Nope. He just has this nebulous dislike (not even hate) of the living and mortals, thinking them mildly distasteful.
The Anti-Monitor has many of these qualities. No real personality, motivations or backstory, just ridiculous amounts of power in one package. Still, part of the concept is that he's so ridiculously powerful that it's difficult to so much as get his attention so there is some reasoning behind his seemingly Generic Doomsday Villain nature.
Similarly Mandrakk the Dark Monitor pretty much just wants to kill everything because he wanted to feed on the Bleed and the Multiverse that existed within it. It didn't help that he was also a Giant Space Flea from Nowhere, unless the reader had already read a particular tie-in.
The contrast between Doomsday and the rest of Superman's foes is touched upon in the story, with Superman fearing he might have to delve into He Who Fights Monsters territory.
These pop up now and then in Invincible. Unusually, they are treated by the writer with all the gravity they deserve: very little. One notable one was vanquished by all the guest stars and supporting characters in the series working together while the series protagonist, Mark, was unavailable. It was a Crisis Crossover reduced to the B-plot of one or two issues of one title.
Bane started out as this, (though he did at least get an issue to explain his backstory beforehand), rolling into Gotham, easily breaking Batman's entire Rogues Gallery out of Arkham, quickly deducing Batman's secret identity, before ultimately breaking his back and, having served his purpose, gets thrashed by Azrael in what almost seemed like a bit of an afterthought. Eventually the writers fleshed Bane out more, giving him an identity beyond being "the guy who broke Batman's back once". Unfortunately, there is also a tendency for some of his portrayals (especially in adaptations to other media) to focus entirely on the steroidal "Venom" aspect of his character and nothing else meaning that once someone cuts his tubes, he goes down quick.
Played straight, then subverted with Anathos from Les Légendaires. In his backstory, he is revealed to have destroyed the original world of Alysia for no other reason than testing the power he just got at this point. When coming back, on the other hand, he explicitly explains he wants to destroy the world as an act of revenge toward the other Gods for trapping him inside the Bearer for so many years. Granted, this isn't an especially complex motivation (especially considering most other villains in this comic usually have some depht to them), but that still counts.
Onslaught was more powerful than anything the X-Men had ever faced, took nearly all the Marvel heroes to beat, had no overarching plan other than "blow shit up" and existed solely to set up "Heroes Reborn", which was later retconned back anyway. Onslaught did have a back story as a psychic entity born from the combined mentality of Professor X (mutants and humans should co-exist) and Magneto (humans will never accept mutants). So he wanted to turn everyone in the world (and later the universe) into a hive mind with himself in control. However, many of the details behind his character were scattered amongst various Marvel comics titles (requiring someone to read all the comics tied into the Onslaught saga for all the details), or crammed into a book released solely as a summary for the Onslaught saga, complete with notes and information on what was planned for the saga from the writers themselves. For some, Onslaught's Generic Doomsday Villain nature made the writers' attempts to focus on Onslaught's plan changing from "kill all the humans so mutants can prosper" to "kill everyone in the world for no reason" much less dramatic that it was intended to be.
Spider-Man's equivalent to Doomsday would probably be Morlun, a villain introduced by J Michael Straczynski during his run. Apart from a few references to his race feeding on people who were connected to animal totems, Morlun had no real backstory to speak of, and his exact nature was never revealed. His personality was pretty bland as well, since he really only wanted to "eat" Spidey and stated that it wasn't personal. For some unfathomable reason, this was the first time a villain had ever made Spider-Man angry, even when guys like the Green Goblin and Doctor Octopus had kidnapped, murdered or otherwise threatened his loved ones. His latter appearances, especially when written by Reginald Hudlin, are driving him towards this trope as well.
Venom started out this way too. Or more precisely, his human alter-ego Eddie Brock did. The alien symbiote that used to be Spider-Man's black suit had motive for revenge and bonding with Eddie, but Eddie himself had never once been seen prior to Venom's introduction, and his motivation for revenge against Spidey was extremely half-assed, with Eddie himself having no personality beyond "I hate Spider-Man!"
Notably, SpiderManTheAnimatedSeries took great pains to avert this portrayal, spending its first several episodes showing how Spider-Man often inadvertantly wrecked Brock's jobs in the course of his battles, ultimately getting him kicked out of his apartment.
The IDW Transformers series turns the Decepticon Thunderwing into the "force of nature" variation of this trope. After he creates his "polydermal shell", the grafting process goes awry, burning out all of Thunderwing's sentience and higher brain functions, which causes him to become ultra-powerful, and go on a rampage across war-torn Cybertron, forcing both Autobots and Decepticons to temporarily ally to try and halt its advance. In the end, Thunderwing is only stopped when Cybertron swallows it whole, a process which only hastens the planet's death (which Thunderwing himself saw coming and the polydermal grafting procedure was an ill-conceived attempt to try and weather the storm it would bring, ironically turning him into the final nail in Cybertron's coffin).
Typically very common in Crisis Crossover events, as writers and artists are quicker to show how powerful their creation is than to make it interesting.
Titan from My Little Unicorn. He has all power and wants to destroy Unicornicopia just so he can spread chaos and destruction over reality, just because. His dialogue is dripping in clichés and there is nothing unique about his appearance at all. Being Stupid Evil and going with the first Saturday morning cartoon plot his minions come up with doesn't help matters.
Shinzon from Star Trek Nemesis. His reasoning seems to consist of "Well, I'm the villain of this movie, so I guess I better mentally rape Troi and destroy Earth." The extreme actions that actually relate to his supposedly well-intentioned goals occur entirely in the opening minutes of the movie: as he was raised by the Remans, he understandably doesn't like their status as the Warrior-Slave Race of the Romulan Empire. But when he assassinates the entire Romulan Senate and installs himself as the new dictator... he's already solved all the Remans' problems. At that point his only real explanation for wanting to destroy Earth is to prove the Remans' superiority over the Romulans and show the galaxy that their Romulan empire is not to be messed with which is somewhat unclear. For a poorly explained reason (to prove to everyone that the Remans are to be taken seriously), he has a super battleship way more advanced than every ship it comes up against. He also got a planet-destroying superweapon from... somewhere.
Nero in Star Trek. His backstory is that, in the late 24th century, his home planet (with his pregnant wife on it) was destroyed in a supernova, which, for some reason means that he wants to destroy every planet in The Federation. To make matters worse, no one ever points out the fact that he's gone back in time a hundred and fifty years before the supernova took place and therefore has ample opportunity to, oh, I don't know... WARN HIS PEOPLE THAT THEIR PLANET IS GOING TO BE DESTROYED.
This is a bad case of All In The Manual, as reading the prequel comic reveals that Nero witnessed the beginning of the supernova, but the Romulan senate refused to listen to him even with concrete evidence. So once he goes back in time, he figures that if that senate wouldn't listen to him, the one he would now face sure as hell wouldn't. In the comic he also works closely with Spock on the Federation science project to prevent the disaster, hearing promises that everything will end up all right... only for it to go horribly wrong. That in turn makes Nero's desire to destroy Vulcan and the Federation more understandable. Spending a decade inside a Klingon Prison after going back into the past didn't help his sanity either.
You like the destruction they cause, but don't much care about them? Sounds like a C-list Kaiju. The better ones havesome motivation and / or are oddly sympathetic, but the ones that never appeared in more than one movie are pretty much this. Whether it's a bad trope, of course, depends on how cool the destruction is.
Rodney Casares from the Peter Clines book Ex Heroes. He randomly turns up with the power to control the zombies, to survive the zombification with his own intelligence intact, and with enhanced physical abilities and stature he never had in life. The most that's ever explained about him is that he used to be a random gangbanger and that he was one of the first victims of the disease, but he is otherwise completely unique and exists for no reason other than to present a massive threat to the main cast.
The Mule, villain in the second book of the Foundation trilogy, is a deconstruction of this trope. He's a (actually rather scrawny)Genre Savvy mutant with potent Emotion Control powers in an otherwise generic space opera setting trying to take over the galaxy just because he can. Of course, for all of his Genre Savvy-ness, he still ends up brainwashed by the Second Foundation.
A classic example would be Professor Moriarty of Sherlock Holmes, who could be considered Doomsday before Doomsday. He's introduced in the last chapter of The Memoirs of Sherlock Holmes and is talked up to be Holmes' Arch-Enemy who is supposedly his intellectual equal, even though we never see evidence of this. He was also said to be "the Napoleon of crime", and had a hand in many of Holmes' previous capers. In this particular case, he was behind a conspiracy bigger than anything Holmes had tackled before, and it ended up supposedly costing Holmes his life. And yet he had little page time and no personality to speak of, only defined by the threat he posed. Of course, he became the Breakout Villain and has since been more fleshed out in adaptations and spin-offs.
Karla from Tinker, Tailor, Soldier, Spy by John La Carre is a Communist terrorist who doesn't seem to have any motivation for his evil ways other than... terrorising people and spreading Communism. What a jerk.
Earlier episodes of Buffy play with the trope quite a bit. In "The Zeppo", the generic villains are never given enough screen time to explain their motivations as that's part of the joke. In "Doomed", like most of the show's baddies, they're a metaphor for something else. Most notably, in "Becoming", Angelus decides to destroy the world just because he can, and so Spike betrays him because he doesn't see how he would gain from the end of the world.
Ditto The Beast from Angel. His status as this becomes a plot point, when they realize he's not smart enough to have come up with his plan on his own, and is serving someone else.
Arthur Petrelli from Heroes is a conscious attempt to avert this, with him stealing Peter's Physical God powers and not using them to cause wanton destruction. Though his lack of motivation or any real plan land him into this trope anyway. He existed to steal Peter's power and as soon as he did that he faded into the background and sat around waiting for Sylar to kill him.
Once Upon a Time: In the pilot episode, the Queen is supposed to be this, untill Snow White says she wants to be Fairest of Them All. It isn't the case, as she wants Revenge, and, later, keeping her power and her son.
The Replicators. Since most of them are machines made out of Lego blocks, they have no personality whatsoever. All they do is multiply. And they just. Won't. Stay. Dead. Though this changed when the show introduced the Human Form Replicators (including the Asurans), which actually had personalities and in some cases became recurring characters. Some were even somewhat sympathetic.
Anubis, known as the most evil of all Goa'uld, his goal goes beyond wanting to rule over the galaxy. He literally wants to wipe out all life in it, using a weapon of the Ancients that sends out a wave that can do exactly that. And since he is practically the only being that would survive this, well... No reason is ever given for this (Anubis doesn't elaborate any further than stating that it's part of his "grand design"), other than that he's evil, although Daniel theorizes he may want to rebuild things in his own design (since the Ancient device Anubis planned to use was also capable of creating life...in fact, that was its original purpose).
Walker, Texas Ranger: The episode "Warriors," from the fifth season, sees the leader of a supremacist group create an army of genetically superior soldiers to help him overtake the law and eventually rule the world. The enforcer of the group fits the trope, as he is easily able to overcome Walker and Trivette – even gunfire by way of DNA that allows him to not be harmed by gunshots. Eventually, Walker is able to defeat this nemesis ... with some help from a genetic researcher, a flask of flammable liquid and a lighted torch.
Mythology and Religion
Surtr, the fire giant who is responsible for the end of the world in Norse Mythology, is probably the Ur Example. He doesn't appear in any myths except the one that tells of Ragnarok, where he and his armies invade Asgard, he kills Freyr and engulfs the world in fire, and even that myth gives him little description or characterization. Still, while he may not appear, he is referred to in numerous other tales of both the Poetic Edda and the Prose Edda. And he's hardly the only Jotunn lacking character depth.
Michelle McCool gets this, in large part due to being a Creator's Pet because of her relationship with The Undertaker. The worst is likely the Piggie James angle - she spent months running down Mickie James all building up to Mickie beating her and taking the Women's Championship... then Michelle won it back about two weeks later and has had no problems with Mickie since. It didn't help that "Piggie" James spent most of the feud getting the crap beaten out of her and being mocked about her weight. Being hated is a Rudo's job but they are supposed to get properly punished to please the fans that now hate them.
Between 2002-2006 in WWE, it was incredibly hard to sum up Triple H's character beyond "World Champion", "Stephanie McMahon's husband", and "sledgehammer aficionado".
Prior to the Attitude/Monday Night Wars era, the "generic doomsday villain"-type storyline was used heavily in the World Wrestling Federation to build up a heel wrestler toward a world title shot against Hulk Hogan. Villains such as King Kong Bundy, Big Boss Man, Akeem/One Man Gang, Earthquake and others spent would spend several weeks on TV beating up jobbers and mid-card wrestlers before their big match against Hogan ... and invariably they would all lose. *
Even The Undertaker took a rare pinfall loss to Hogan in the fall of 1991, prior to winning the title.
The outcomes of these matches became so predictable it was as though these fearsome bad guys were simply generic bad guys who, after screwing with Hogan, weren't so big and bad after all.
This was the main problem with WCW's New World Order angle (in all its incarnations): the fact that this faction of bad guys was so elite that they never lost. Even the nine-month buildup leading to the defeat of Big BadHollywood Hogan by Dark MessiahSting was tarnished by the fact that Sting was pinned and lost before the match was restarted (because evil referee Nick Patrick had supposedly done a fast count that, in reality, was closer to a slow count).
Indeed. The original outcome was for Sting to be pinned by fast count thanks to Nick Patrick's interference, therefore creating a valid reason for the match to be restarted by Bret Hart, who was one of the hottest commodities in wrestling at the time and was making his big debut in WCW at the time. It is rumored that Hulk Hogan bribed Patrick, a notoriously corrupt ref, to intentionally slow down his count so that the main reason for restarting the match and giving the victory to Sting would be null and void. This created a great backstage controversy that basically killed all of the momentum Bret Hart had in his entrance to WCW, which was supposed to be the last major blow against the then-WWF to kill WCW's chief rival for good. However, thanks to the bullshit pulled backstage by Hogan and his little clique, among other things, the WWF was able to rally itself going into 1998 and ultimately crush WCW at the end of the Monday Night Wars.
The capper was that when Sting slapped on the Scorpion Deathlock, Hogan never tapped out. Supposedly, Hogan was yelling "I quit" but none of the cameras or mics picked this up. After almost two years of dominating WCW and nine months of building up Sting as the Bad Ass savior of WCW, seeing the villainous leader of the nWo giving up in agony against Sting should have been a Crowning Momentof Awesome for WCW but it instead signaled what was going to happen to the company later on.
Leviathan, from the Dungeons & Dragons supplement Elder Evils, is a serpent made of the leftover chaos of the world. If it wakes up, the world will cease to exist. Interestingly enough, it's Chaotic Neutral, not evil - destroying the world is simply what it does. The campaign layout provided has the "good ending" condition being putting it back to sleep, not killing it, as it's literally thousands of kilometres long and hence not capable of being fought by human-sized characters. Besides, killing it might cause it to destroy the world in its death throes. And if that didn't happen, its death might still irreparably damage the balance of order and chaos and destroy the world anyhow.
The Terrasque is similar in most respects.
The Big Bads of the Old World of Darkness tend to be treated similarly, but then again, the manifestation of any of them was explicitly a sign of the apocalypse.
The Tyranids suffer from this to an extent. They're a Horde of Alien Locusts that shows up, eats everything on a planet and uses the bio-mass to make more Tyranids to repeat the process on the next world. Certainly dangerous, certainly terrifying, but they're essentially animals. The most nuance to their backstory is the suggestion that they're attacking our galaxy because something even worse is chasing them.
The Archdemon and darkspawn of Dragon Age are a rampaging force of nature, but they frame a backdrop for more complex and nuanced character conflicts. Only after confronting the antagonists native to Fereldin can the player wrap up the overarching invasion-of-evil epic.
The darkspawn are partly motivated by the need to eat (often people) and reproduce, since the only way darkspawn CAN reproduce is by abducting women and transforming them into broodmothers.
They gain more depth in Awakening. One faction of the "Awakened" wants to awaken the rest of the Darkspawn and create a place for themselves in the world, though they are hampered by Blue and Orange Morality. Another faction follows an insane Death Seeker who resents her new sentience because it cuts her off from the song of the Old Gods.
Zemus from Final Fantasy IV wants to destroy all life on the Blue Planet. There's some handwaved justification that it's so the Lunarians can move in, but none of the other Lunarians want this, so it's still pretty pointless.
More specifically, none of the other Lunarians want the humans killed to make room for them. They were "sleeping" in suspended animation waiting until the humans are advanced enough for the Lunarians to join them. Zemus seems to have concluded that if the humans are all dead, it wouldn't matter if the other Lunarians liked the outcome: they'd still have no reason no to just go down to the Blue Planet. And Zemus thought he was too powerful to be in any danger of punishment.
The Unbound in late Geneforge were designed to spread a wave of equal-opportunity devastation over the world, with the expectation that the Shapers would be caught off-guard and demolished while the Rebels bunkered down and waited it out. By the last game, they're everyone's problem.
In Guild Wars Nightfall, Warmarshall Varesh wants to wake a dark god and its legion of demons, unleash Torment upon the world, and bring about eternal night and suffering because... hmm.
Kid Icarus: Uprising features two: The Aurum, a Horde of Alien... uh, bees that "are created from, and return to, nothing." and The Chaos Kin, a pure manifestation of evil that takes control of a host and slowly devours its soul. Both are presented as serious threats; the former requiring all the warring factions to do an Enemy Mine and team up, and the latter being a major Knight of Cerebus that causes the game to take an unexpected plunge into Darker and Edgier territory.
Several of the villains in the Kirby series, like Nightmare, Dark Matter and Zero, Drawcia, and Dark Mind are this, since they're presented as the villains for attacking Kirby's home planet with little revealed motivation or characterization to go with it.
Odio in Live A Live is a reincarnating force of destruction. At any point in time there would be a hero to rise up, Odio will manifest during that time, causing terror, death, and annihilation, and directly oppose the hero. Odio will always bear a similar-sounding name that fits with that time period (such as Odi Iou for feudal Japan or Odie Oldbright for late 20th century America), making him easy to spot for the player, but the idea is that while the heroes may consistently defeat Odio, it will always rise up again in some other time. ... Except no, he isn't that at all-he's actually the mind of Fallen Hero Oersted, who has very well-defined motives. The reason he opposes the protagonists, as it turns out, is because he takes umbrage at their idealism and wants to prove a point to himself.
Dr. Regal from Mega Man Battle Network 4. His objective is to make a meteor collide with the earth, which would destroy it. The only motive he has is because it's evil and that's something an evil person would do. His Navi is also completely one-dimensional, caring only about evil. Even ShadeMan has more personality than the two combined!
It wasn't lost on the developers, either, it seems. Dr. Wily, his father, and still a bastard, is ashamed of him for it, giving him Laser-Guided Amnesia so he will stop doing things just to be evil in 5. That's right, even the Big Bad doesn't care for it.
Justified in the case of Omega of Mega Man Zero 3. He's a Reploid simply programmed to kill and cause nothing but destruction.
Mother 3 manages to drop the "Generic" from this trope, and hard. The Big Bad of the game is Pokey Minch, now an emaciated batshit crazy Man Child who could be anywhere from 10,000 to 100,000 years old due to his abuse of the Phase Distorter. Even he doesn't really know why he wants to destroy the world, but it seems to sway all over the place between loneliness, jealousy, boredom, and insanity.
In Myth the ultimate Big Bad is the divinity called the Leveler. His modus operandi consists of, at regular intervals, take over the body of the hero who killed his last incarnation, resurrect and corrupt other heroes of ages past, and then try once again to destroy all life on the planet and rule over the dead lands. Why? It's not really explained.
The title characters of the Overlord games are meant to be classic stereotypical Evil Overlords and thinly-veiled Sauroncopycats. While the characters are often doing evil and the players do get to determine how evil they are, it's really Evil Chancellor Gnarl that carries their villain cards for the Silent Protagonists. What makes it worse is that, in the entire time you're trying to build yourself up as the incarnation of evil, you spend the entire time fighting heroes... Who are now the corrupted embodiments of various sins, so you're not even being THAT effective a bad guy. While it could be said that by defeating them you prove you are the "most evil", the Karma Meter in the game basically sways between (very!) benevolent dictator and Omnicidal Maniac. At least in the sequel, the "hideously evil" path means you have to slaughter everyone in the villages you took over while the "domination" path meant magical Mind Control.
The modern shooter genre has been accused of producing these frequently (usually in the form of Russia), but Solomon of Battlefield3 probably takes the cake out of all of them. While Zakahaev and Makarov had the less-than-original motivation of restoring Russia's status as a superpower, Solomon wants to nuke Paris and New York and start World War III because...ummm....he's evil?
Goblins has Kore, a legendary Dwarven Paladin who kills anybody even vaguely connected to the "Evil" races, especially the women and children. Why? He's not saying, but his Armor Class is ridiculous enough to let him get away with it.
Homestuck's Jack Noir ends up becoming this. Starts out with a good bit of personality, but once he takes over as Big Bad he just starts wrecking things for no real reason... none that we know of, anyways. Word Of God describes his personality as basically being buried" beneath his power, and describes him as akin to a raging dragon, so it's safe to say this is a deliberate use of the trope. A later scene from Jack's perspective clarifies it further: once he's gained enough power to become the Big Bad, he's just become bored. Most of his evil acts have just been him trying to come up with something to do with his new power.
The closest thing to a reason that he had was that he was fed up with being forced to wear his harlequin uniform.
And then his rampage across the trolls' session was out of Unstoppable Rage after Jade dies again.
The Snarl from The Order of the Stick. Not a major player in the story, but ready to obliterate everything if it ever gets loose. Or not: it will likely end up deconstructed like many tropes in OOTS. We've only heard about the Snarl in two flashbacks told by different characters with an agenda that contradict each other, and one of the main characters has admitted he probably doesn't know as much as he should about this alleged threat to the world.
Mecha Sonic from Super Mario Bros Z fits this. Even when he was just Metal Sonic, Eggman didn't give him a personality beyond "make Sonic dead" and "blow up anything in my way", so he's running off nothing but what he's known how to do all along.
"You're overpowered, you don't have a hook, and quite frankly, you're boring."
— "The Director"
The Lich from Adventure Time has no real characterization outside of his goal of "kill everything"-somewhat justified as it's revealed that he became what he is now because he was at the epicenter of basically a nuclear explosion, and thus wouldn't really care about much more than "kill everyone."
D.A.V.E in The Batman may well be a deconstruction. He is a robot programmed by Dr. Hugo Strange with the memories and abilities of Batman's worst foes for the sole purpose of giving Batman a challenge. He proceeds to easily curbstomp Batman and steals ALL of Gotham's money just to commit the ultimate crime, but is defeated when Batman asks him to explain his origin story. Since D.A.V.E believed that he used to be a person, he basically went catatonic after realizing that he had no backstory of his own.
Doomsday in Justice League showed up for the sole purpose of starting a fight, and then getting lobotomized to show how dangerous the Justice Lords are. In the sequel series he is retroactively given a back story, but it doesn't change the fact that he was originally created as this.
The Justice League Unlimited version of Brimstone, basically a superweapon that went berserk for no identifiable reason other than to give Green Arrow a reason to join the league.
Atomic Skull from Superman Vs The Elite has no motivation for his violence. Why is he killing people? To draw out Superman. Why does he want to fight Superman? Because it's what he does, apparently.
Many of the one-shot villains on Megas XLR are like this. Ender, who existed to "end" things, and Gurrkek the Planet-Killer really fit the bill, however.
King Sombra from My Little Pony: Friendship Is Magic's season 3 premiere. He is built up as being a huge threat to the Crystal Empire, and is also revealed to have set up an intricate security system to prevent anypony from getting the crystal heart, but other than that, his characterization is noticeably thin, especially in comparison to the show's other villains, and there is barely any backstory for him to speak of. This isn't helped by him speaking very little, eliminating a way for the viewers to know his personality. According to Word Of God, this was partly intentional, as Sombra was intended to be a terrifying, menacing force lurking over the entire situation rather than a character. It's just that the writers weren't permitted enough freedom to make him effectively menacing.
A few of the Sushi Pack villains fall into this, most notably the Titanium Chef, who wants to spread chaos throughout the world for no other reason than he has a book that tells him how.
Dark Kat flirted with this in SWAT Kats. He always wanted to "build a new city" over the old that would serve as a "capitol of crime", but it often seemed like he was more interested in destruction itself, as in his first appearance where he tried to nuke the city. Another applicable villain under this heading would be Volcanus, the fire demon, who never even spoke, just woke up and made a beeline for the nuclear power plant...
In Teen Titans Trigon was easily the most powerful villain of all, seeing as how he destroyed the world approximately 12 seconds after entering our dimension. However, being the "incarnation of evil" doesn't seem to leave much room for a complex or interesting personality. Luckily, every episode with Trigon in it also had Slade around acting as The Dragon.
Most of the villains in the show seemed to be wreaking havoc just 'cuz. Though it doesn't help that the show had a general aversion to origin stories.