Starscream's murdering of Cliffjumper. Usually one of the good guys dying in a kids series is rare or dramatic. Not here. A villain simply tears out a vital organ and casually orders his goons to clean it up in the first ten minutes of the series.
Zombie Cliffjumper in the second episode of "Darkness Rising".
Megatron's zombie army.
Starscream: as if killing Cliffjumper in the first five minutes of the series wasn't enough, everything he says and does in Episode 3 is just terrifying. Three words: "Bring the prod."
Fowler's interrogation in episode 4 was pretty messed up too. Never thought Starscream could be that menacing. Primus almighty.
When the kids get mixed up in an Autobot vs. Decepticon fight for the first time. The scene is much scarier than it is cool: the first explosion muffling the sound, Vehicons getting their heads ripped off while all of the robots are inches off from stomping the kids in the chaos... and the camera is positioned at Raf's height, showing just how much worse of a war zone, nay a scuffle between giant robots is from a human's perspective.
The fact that they're incredibly tiny and caused three Autobots to pull their guns out on one should tell you something about them.
Bulkhead's description of what they do to a Transformer is truly terrifying:
"Miko, you haven't seen a swarm of these things devour a bot. I have. They pick you apart from the inside out, going for the small juicy bits first, fuse by fuse, circuit by circuit, 'till there's nothing left, and I mean nothing. Not even your optics."
As a bonus, remember that a fair amount of the human population has metal in their bodies. Pins, plates, braces, the works. Nice, warm, metal.
We get a up close viewing of exactly how much damage Scraplets can do on an Insecticon, completely dismembering the beast while it was still alive and shrieking.
Energon Harvester used on Cybertronians. Liquid Energon is essentially their blood, so its a device which sucks your blood out right through the skin until you die. In a matter of seconds. *shudder*
Scarier is that it was supposed to be a mining tool.
Knock Out nearly killing a driver for something as small as scratching his paint job seems unsettling.
And at the end of the episode, when Starscream decides to give him a "cosmetic" punishment. Scratching out the finish might be minor for some, but it's a whole lot scarier when the finish is your skin.
Optimus and Arcee slowly freezing to death, trying to keep their spirits up as they essentially wait to die is terrifying. Seeing a Peter Cullen voiced Optimus Prime so helpless and near death makes this cross over into Tear Jerker territory as well.
It happens again in "Sick Mind", where he ends up sick due to Cybonic Plague, dying.
Airachnid. Think Blackarachnia with "sexy" switched out for "TERRIFYING!"
Dear God, in her debut episode, it's shown that she tortured Arcee ala flashbacks and has come to Earth to seek human trophies, and Jack just happens to be around, which delivers a fine and very tense chase scene. Yeah, it's one of the darkest episodes in the series by far.
And in case she wasn't disturbing enough, rather than finding endangered species to hunt, she makes them. So she basically decided genocide would make a nice hobby.
Oh, and one of her favorite methods of attack? Tunneling under the enemy and, once beneath them, opening the ground and burying them alive.Claustrophobic much?
Also, she has a spine-chilling theme song which helps make her even more terrifying.
In "Sick Mind," the corpses of the Autobots infected by the virus.
In "Out of His Head", the now revived Megatron dragging off Starscream to do presumably horrible things to him.
The next episode shows Starscream badly damaged, but given medical treatment specifically so that Megatron can gloat over it.
Megatron's booming voice announcing his return is perhaps one of the most terrifying moments in the series.
One of Megatron's flashbacks is of Starscream ripping out the Dark Energon shard from the Decepticon leader's broken body, only this time it's from his point of view; After the shard is torn out, Starscream turns to the camera and gives the most terrifying Slasher Smile he can make. Just look at it.
How about the possibility of being trapped in an alternate dimension with a giant robot zombie chasing you in circles for all eternity sound?
You can't even call your friends or family to save you! Granted they bypassed that by texting, but still.
It gets even worse when they blow off Skyquake's arm, and it starts chasing them on its own much faster than the whole bot was.
In "Operation: Breakdown", MECH manages to capture Breakdown. Turning off his pain receptors, they plan to cut him open alive, while he's still awake. Decepticon or not, the look on Breakdown's face is one of pure horror.
And the fact that they remove one of his eyes too...
As of "Metal Attraction", it seems that he's not getting a replacement despite the rest of his damage being repaired. Judging by Megatron's attitude towards Breakdown, this may be an intentional punishment for getting captured in the first place.
Setting makes the nightmare better, always. And... well, the abandoned city in the Chernobyl evacuation zone certainly doesn't hurt the rest of it, either...
The death threats to June must certainly have scared people. As well as the fact that Silas and Airachnid found Jack and June by looking at a social networking page, something that has happened in real life.
Megatron comes across as pretty damn terrifying during "Rock Bottom", and not just to Starscream. Even when he's trapped under some rubble he STILL manages to taunt Jack for not taking advantage of the opportunity to kill him. And that whole ending sequence just... guh.
It's a blink and you'll miss it notice, but you'll notice Megatron actually smirk right before the episode cuts to credits. And that smirk makes him all the more terrifying.
While we're on the topic of Megatron, the ending of "Sick Mind" gives us this gem.
Going back to "Rock Bottom", Starscream's tormenting of poor, suffocating Miko is just horrific.
Back in episode 6, Megatron's nearly dead body floating in space... And then, after Starscream plucks the Dark Energon from his spark, Megatron briefly awakens, with what appeared to be an absolutely frightened expression. Megatron was almost pitiable in this situation
Most parents will feel very unnerved when the show almost averts Infant Immortality when Megatron almost kills Raf with Dark Energon, made all the worse as Raf's easily the youngest of the three. Then there's the fight and Megatron's Slasher Smile.
Megatron sees a hallucination of Unicron. He's very realistic due to the fact that a character's worth of detail is being poured into making a quarter of his face. And he's looking straight at you.
Now "One Shall Rise" has aired its first part. Unicron is waking up. The Earth formed around him, and if he wakes up and stretches his legs, he WILL destroy us. Worse is his ability to make himself out of bits of rock. Destroy one of his rock forms, he'll make manycopies and control them all, then beat the ever-loving crap out of you.
Megatron's Evil Laugh, which is completely terrifying.
He sounds so happy. Like, "Hooray, it's my birthday!" happy. Brrrrrrr.
Oh, and let's not forget that Unicron looks horrifyingly demonic, possibly even more so than he did in his debut appearance. Very fitting that the Chaos Bringer should look like the devil.
In other words, Unicron IS Earth. Remember when you were a kid watching Transformers and the thought of a planet sized monster from space was scary? Well, you've been living on one your whole life!
At the end of "One Shall Rise, Part Two", Unicron is the Earth's core. The fact was established beforehand, but seeing it for the first time is creepy. Then there's a giant eye that suddenly reactivates, stares round for a few seconds, then stares straight at you.
What gave this editor the chills was the fact that you could hear Unicron's goddamn heartbeat as Dark Energon visibly pulsed through the slumbering beast's veins.
The season 2 opener has Knock Out engraving a Decepticon symbol onto an amnesiac Optimus Prime.
See all that debris laying around on Cybertron? Look closer: That right there is an arm. And over there's a leg, and over there ...
The Insecticons are basically the Cybertronian version of Tyranids, just serving as Megatron's sentries.
Even though the Insecticon was bad, his fate was unnerving at best. Remember way back when Bulkhead said that Miko hadn't seen Scraplets devour a bot? Now we have. To clarify, in their debut episode the Scraplets simply started gnawing on you. In this they all start chewing the Insecticon's joints until it is nothing more than a torso and head shrieking in pain.
It's even worse. The one Insecticon Airachnid found? Turns out it's a scout and that it was guarding a whole nest of them
The worst part about that? Megatron had difficulty taking down one! By the time he finally killed it, he collapsed at the mercy of the Autobots! Imagine how strong a whole army of those horrific things can be.
The battle between the rogue Insecticon and Megatron was also pretty brutal. At one point it looks like the Insecticon cuts Megatron causing him to leak energon. Also Megatron kills it by cutting its head off
Airachnid's killing of Breakdown. While the death is offscreen, you do get to see... what's left.
Not to mention his bloodcurdling scream, which is even worse than Starscream's in "Operation Bumblebee, Part 2".
In "Nemesis Prime", we get our second near-death of a human, Silas. Not only that, but the implication that MECH will keep him alive by seemingly installing his consciousness into a rebuilt corpse of Breakdown can also be pretty unnerving.
Even before that, there's Agent Fowler at the beginning of the episode, when Nemesis, who Fowler believes to actually be Optimus, tries to knock his car off the edge of a VERY tall bridge into a rocky ravine. Fowler's terrified cry of "Prime, NO!" just before his car goes over is pretty jarring, considering Fowler has never panicked like that before.
Nemesis Prime is this, as can be expected. Highly looks like an undead version of Optimus, goes on a terrifying rampage on a military base (and almost certainly killed the majority of the military personnel, if not a fair number of them), takes down all the Autobot team par Optimus with horrifying efficiency and then guts Optimus.
MECH in general has dived head-first into HONF territory. If it's one of their projects, it's guaranteed to be at least eight different kinds of sick and wrong.
The nest of Insecticons was bad enough, but "Armada" (not to be confused with the first part of the Unicron Trilogy) shows them in full force, targeting the Nemesis.
The worse part is that now, they're loyal to Megatron again.
Airachnid getting locked into stasis can be a little unnerving.
Starscream pointing a missile at his downed clone was incredibly chilling, especially since he spoke in a low, dark growl while doing so. Steve Blum really knows how to work a full range of emotions.
"Armada" also has Airachnid telling Arcee to make it hurt when Arcee kills her. Didn't know Airachnid was masochistic... and it's disturbing as hell. Thankfully, Arcee doesn't do it.
In the trailer for "Flying Mind", Megatron is shown with purple eyes at one point, possibly implying that he is using Dark Energon again.
Not only that, but the ship is seemingly alive. Considering Exodus implied that Trypticon's body was reprocessed and his mind essentially lobotomized...
The ship putting everyone on board into stasis was also unnerving to say the least. Even if everybody was eventually restored...
When Knock Out wakes up from stasis, he sees Jack trying to remove the transfer drive from the control panel. He then puts on a Slasher Smile, activates his drill, and then starts inching it closer to Jack. Thankfully, though, Ratchet arrives before Knock Out can do any damage.
Knock Out: Say "Ahhh..."
Starscream, trying to replace his t-cog with one he swiped from his traitorous clone by performing surgery on himself. As in, he's fully conscious. And then there are those few tense moments when he's holding that drill over his torso, trying not to lose his nerve. Mercifully (for us and in-universe), he's interrupted before he can start.
Soundwave during "Triage". The little bit of Soundwave we normally get is eerie enough, but Triage is the first episode to give him heavy focus. And his silence makes that focus damn scary.
"Triage" also gives us a gravely injured Bulkhead being hurled back through the Ground Bridge. How it happened isn't clear at first, but "Toxicity" shows that he's just had a vicious fight with the Insecticon Hardshell.
Anyone ever noticed whenever someone or something hits Soundwave, he doesn't react? When Wheeljack scratched his visor with his sword, Soundwave didn't even make a noise. It's quite unsettling.
When Soundwave arrives to collect Laserbeak, it seems like he's taken the bait, only for a small piece of Laserbeak to make itself known to him... right behind the same rock as Ratchet. Thankfully, Soundwave's tentacles avoid the doc altogether.
Let's just say it: Soundwave in general. So much so that even the other Decepticons share in our fright.
In "Toxicity", we have the Tox-En, which in short, is the poisonous Cybertronian equivalent to Kryptonite. Throughout the entire episode, Bulkhead has to try and handle this, but it gradually starts killing him. We get treated to a lovely first person view of him blurring and being unable to see what he's doing, all while Hardshell is kicking the crap out of him.
Oh yeah, and it turns out that he was gravely injured when Hardshell shot him in the back, after he climbed out the volcano.
The brutal beating of Orion Pax (who doesn't even try to fight back) by two Vehicons who are only too happy to deliver it in "Orion Pax, Part 3."