Not even the future is safe from nightmares
The series, though featuring a colorful cast of future superkids trying to follow the example of Superman, has a wide variety of nasty scenarios and horrors beyond space and time. Even with a legion of superheroes, the future can be pretty bleak.
- Much of Brainiac 5's transformations come off as Body Horror when in use due mainly staying in humanoid form, making him come off as a friendly Humanoid Abomination. Bonus points when his head is removed and he simply sprouts tendrils from his head to move around.
- Dr. Mar Londo. Timber Wolf's father who might be one of the most evil parents in animated fiction considering he comes off as a kindly scientist simply looking for his son before it's later revealed he turned his teenage son into an Ax-Crazy lupine monster as part of his twisted experiments to make perfect soldiers and created a whole forest of creatures by tampering with indigenous wildlife. According to Saturn Girl, they are in a constant mental anguish. He also frames his son for murder using a clone, tries to force him into servitude, and then kill him to start from scratch when Timber doesn't play along. Unlike the other monstrous villains of the Legion, he looks completely normal and has a sizable reputation to protect himself. Not to mention he goes about it with complete dispassion For Science! and with such casual glee that it resembles something Shou Tucker would pull off, but worse.
- Alexis Luthor's Lack of Empathy can be pretty off-putting. Considering she goes from a Lonely Rich Kid to Ax-Crazy Yandere trying to kill off Superman and his friends without skipping a beat. All because Superman stopped wanting to hang out with her to help his team. The fact she's voiced by Twilight Sparkle does not help at all and shows she'd be as brutal as her ancestor Lex Luthor if the show continued.
- Dark Bombs. Timed explosives that release tiny specs of dark matter that when detonated can destroy half a planet using a miniature black hole in an instant. One is used to try and kill Phantom Girl's mother in a charity race and Superman is nearly sucked into it at the last second.
- Fear Factory. Lost in a galactic storm, the Legion arrives on an abandoned space station called Quaver-Mass XII hosted by strange hosts that is disguised as a rest stop despite being on the forgotten reaches of space. The place is lined with paintings of screaming figures and brings to life the fears of those who stay in it using realistic holographic simulations. Turns out Quaver Mass is a living station that captures its victims when they scream to feed on their fear indefinitely as an energy source and holds its victims in a suspended state of terror. The more knowledgeable of horrors and phobias you are, the more likely you are to be taken out. Like Bouncing Boy, a horror movie buff, whose horror flicks are brought to life to terrify him. No to mention even if someone tries to damage the station to escape, it will repair itself to stop people from leaving. It would have captured the whole team if Brainiac 5 hadn't essentially sacrificed his life to stop the station and was essentially killed when Superman destroyed the station's CPU at his request. Thankfully, Brainy had a backup drive to revive him just in case.
- Drax. A crazed Kryptonian teenager accidentally released from the Phantom Zone by Superman who plans to release his fellow prisoners. He's Beware the Superman incarnate, loves to cause wanton destruction, and is immune to Kryptonite.
- Brainiac 5 undergoing literal brain death in Brain Drain. He's literally losing his mind and his intellect due to an event native to his species, is aware of it, and is clearly terrified in his Moment of Lucidity when he's not rambling like a maniac.
- Season II starts off even bleaker. Superman X shows up demanding help and comes from Bad Future after an apparent Golden Age of the 41st Century where the world is being reduced to a bomb-out wasteland by Imperiex who is a nearly unstoppable nearly invulnerable maniac who's killed trillions already. He then manages to escape to the 31st Century where his actions in the past causes a literal Ret-Gone to the timeline via universal collapse and antimatter bubbles, killing everyone who was living at the time including Superman X's robotic surrogate parents.
- Triplicate Girl watches one of her copies get caught in an antimatter bubble and essentially watch herself get wiped from existence. This serves as a Break the Cutie moment for the rest of the show.
- In Chained Lightning, Lightning Lad gets his arm ripped off by Imperiex's energy cannon and undergoes a nasty Superpower Meltdown with lightning arcs spewing from his arm socket.
- The fate of Ayla, Lightning Lad's sister, in the episode. As a child, she was struck by energy from Lightning Beasts that gave her brothers Lightning Lad and Mekt their powers, and thought to have been incinerated. Instead she was turned into pure energy instead, spent ten years in the state accumulating energy to become a giant electrical energy cloud, and kept herself sane by singing herself a nursery rhyme taught by Lightning Lad.
- Chameleon Boy undergoing Shapeshifter Identity Crisis in Who Am I after Brainiac 5 imprinted the personality of the Ax-Crazy Persuader onto his brain so CB can convincingly shapeshift as Persuader as a spy against Imperiex. The imprinting worked too well, and the personality stayed in CB's brain even after he went back to normal and Brainiac 5 hypothesized, he could stay that way forever! Superman of all people was so pissed at this he tried to pummel Brainy on the spot as punishment.
- Ironically enough, the shapeshifter Ron Kar may have been in a similar position. Though he was transformed into the genuinely kind, heroic and selfless Superman. It's never made clear if he willingly volunteered to go through with Imperiex's infiltration plan, or if he was forced into it.
- Terra-Man in Unnatural Alliances is a disturbing character given he resembles more of a cowboy-themed Terminator that can regenerate from nearly any damage than a typical bad guy. He doesn't give up and even being trapped inside a planetoid only slows him down for short time. Worse is that he's actually a Well-Intentioned Extremist from the same future as Superman X sent back in time to kill a child that's eventually responsible for making the technology that would create Imperiex. Superman X briefly agrees with him and preps his heat vision to kill the scared child before relenting. He fights until the skin is melted off his face (as seen in the page image) and it takes both both Superman X and Imperiex working together to put him down for good.
- Things reach their lowest point in the "Dark Victory" ending where Brainiac 5 fully succumbs to his possession by Brainiac 1.0, curbstombs the LOSH, and sends Superman screaming in agony into space by fusing a Kryptonite crown to his head before he supposedly dies from poisoning. He then kills Imperiex and goes about turning whole planets into data and nearly atomizes the entire Legion. The series ends on an unsettling cliffhanger as Brainiac 5 returns to normal but leaves the Legion while the evil husk he left behind takes a new form to become Brainiac 6.0. Even worse is that the series ends after that point with Brainiac 6 still at large in a weakened galaxy."Evil does not die. It evolves."
