Nightmare Fuel / Samurai Jack

If you watch the whole series without one squeak of terror, then you have more gumption than Jack himself. Some episodes were entirely built around Nightmare Fuel. Even the episodes not revolving around Nightmare Fuel have scenes that are traumatic, the frequent robot carnage that the censors let pass in every episode occasionally goes way beyond the borders of "not too bad;" once you reach dismembered robots impaled on spikes, things have gotten bad.

  • Don't let the Laughably Evil Large Ham act fool you, Aku himself suits this.
    • Especially his assault on Jack's home city in the first episode. He shows up looking bored, the garrison attacks him, and finally he smiles entertained as he wipes them out with the very arrows they shot at him, and then he starts attacking half-seriously.
    • In the second episode, there are silhouettes of crucified, intellectual dogs, and it's implied that they are dead; Jack's reaction upon seeing it is entirely justified. Aku has been doing this since Jack's original time period to multiple races throughout multiple galaxies. For thousands of years. That's horrifying. It makes you wonder if the universe was better off with the original abomination...
    • The two-parter explaining his origin adds to his terror. Apparently, he started out as this freaky monster inside the earth that would send large, deep cracks through the ground. The cracks were filled with him as he took the form of a tar-like substance, and he would then absorb living creatures to get stronger. At one point, a man calls out for his dog, goes to the back of his house, and sees one of the cracks filled with Aku-goop, and half the dog's leash sticking out. Doubles as a Tear Jerker when we hear the man's anguished and horrified screams.
      • When Aku crashed to prehistoric Earth, he took the form of a meteor that burned nearly all of the dinosaurs down to charred skeletons, then proceeded to gobble up the few remaining survivors. The carnage is abominable.
      • When Jack's father goes to stop Aku, charging into the forest of black, spiky trees with an army of samurai in tow. As they get closer and closer more trees burst up from the ground, and we hear samurai start screaming as their horses (now riderless) run by Jack's father. And then, after Jack's dad wakes Aku, Aku ties him up, slips into the ground, then pops back up by his kingdom and attacks it. Coupled with the guy's horrified face and the Big "NO!" that follows, imagine how the people in the city felt.
      • During the final battle between his father and Aku, Aku slips into the armor of fallen soldiers and makes clones of himself to surround him. They all promptly laugh at him and then just... stop. It's surprisingly unnerving.
    • Worse than Aku is his Bad Future world he teleports Jack to. No one knows Jack, and most of the people either worship Aku or are slaves. It makes one shudder to even think of living in a Bad Future controlled by a Reality Warper master of darkness.
    • Even one of the most hilarious episodes where he's involved merely paints him horrific in a different light. He rounds up kids from within a capital city, with no reason given to them or their parents. The room they're led to is large, red and spiky as always, but has monitors of adorable, yet... off animals, which eventually switch off. The camera focuses on a large red throne in the room. And Aku just appears. No fanfare, no flashy effects, no booming monologue. He's just there. This is how he reads propaganda stories to children.
  • An angry Jack is a terrifying Jack. The third episode (titled "III" if watched individually, since it was actually just the third part of the series' Pilot Episode) has him become a rageful, screaming warrior amidst all of the injuries and the beating he took from Aku's drones as he practically is covered in oil. Even the drones are terrified of him, before he promptly slaughters them all.
  • "Jack And The Lava Monster". As Jack comes closer and closer to reaching the end of an increasingly lethal series of traps placed by a cursed warrior, you see dozens of skeletons strewn about his labyrinth of death, killed in brutally horrific fashion when they each made a lethal mistake on the way in.
    • Worse still, after Jack breaks the curse on the warrior, he returns to human form- but the entire time he was locked away in that demonic prison, he was separated and left untouched from the natural flow of time. With the curse no longer keeping him filled with vitality, the effects of millenia wearing down on his physical body are finally unmasked- he reverts into a frail old man in an instant and dies. Fortunately, he's carried off to the afterlife paradise of Valhalla to live in eternal bliss.
    • Even earlier, Jack is traveling through the scorched countryside that was once the Lava Monster's home, implied to be in Norway. It's bleak, cold, and littered with ash and corpses. On top of that, there's an ominous voice constantly beckoning Jack to follow it.
      "Come... Come...!"
  • Episode 15, "Jack's Tales", has Jack encounter a family of metal-eating robots. The robots, in a fit of hunger, rip each other to shreds, and the insides of the robots look just graphically enough like human flesh to creep you out.
  • The episode "Jack and the Ultra-robots" is worth mentioning, especially the second city. Mutilated robots with horrific faces strewn about, some of them on pikes, and oil EVERYWHERE.
    • Also note that they didn't just attack other robots, they destroyed two other towns, one with little cat-like creatures and another with a population that bore a resemblance to The Sand People. The latter of which is notable in that Jack encounters no survivors.
  • Demongo, dear God. Not only is he an Eldritch Abomination, he steals the souls and keeps the skulls of all the warriors he's slain. Skulls that he wears on his chest. Skulls that he can toss out to summon the ghosts of the fallen warriors to do his bidding, all of which have creepy blue mind-control eyes.
  • The creatures that Jack fights in "Chicken Jack" ranged from downright creepy to outrageously grotesque. And this was a lighter episode!
  • "Jack And The Zombies". Some of those zombies were just plain freaky, like the long-armed zombie and the one that possesses Jack's sword. And when he falls into the crypt... that wail.
    Aku: Oh, Samurai? Where are you, Samurai? You can run, but you cannot hide, 'cause I can smell your blood!
    • The way Aku's voice changes for those last five words just really pushes his creepy-meter to the red.
    • Speaking of the graveyard episode there is a little bit of Fridge Horror that makes Jack's 'battle', and by battle I mean simply trying to survive, against Aku even more frightening. The form that Aku takes to finally overwhelm Jack is a huge black mass similar to the abomination he was a part of. Just a horrifying reminder that even though he's gained sentience and likes to toy with people using different forms, he can become a simple unnatural force if needs be.
      • His close up as he's about to stab Jack, his eyes look creepier than normal.
  • And the Minions of Set episode, it's only against three beings. But these are creatures that Jack himself cannot stop. Any cut he makes the limbs grow back instantly and the Minions continue the chase. Jack is forced to run and go on the defensive for the rest of the episode as he tries to locate artifact pieces that will help defeat the Minions. Nearly getting killed in the process. To say it's tense is an understatement.
    • Jack had to rely on the power of a god to destroy them. The god himself, Ranote , was pretty creepy as well in the fact that he did so with very little effort, the fact that he towers over Jack, and that he does nothing but stare at Jack, not even speaking when Jack asks him if he knows a way to return to his own time.
      Jack: These creatures are more powerful than anything I have ever encountered...
  • Jack follows a little girl to an old, decrepit house. He receives several nightmarish visions about what happened to the various family members that used to live there, all of them appearing to have been killed by some faceless horror. Not even Aku, just some creature with a sadistic streak. And that's only the first half. What really seals the deal is the cacophonic distortion in the "other realm" Jack ends up in, which sounds like something you'd get if you blasted really loud music out of your speakers at full volume.
    • The Haunted House seriously needs to be seen to be believed. The creepy visions Jack keeps seeing to some unnamed thing attacking the occupants of the house, the eerie tranquility in the fake tea room, not to mention that, unlike most villains who appear on the show who all either work for Aku or are involved with him some way, the Demonic Spirit has nothing to do with Aku. It's just... there.
  • "The Aku Infection". Aku spreads some evil that infects Jack and soon starts to look scarier and scarier as it goes on.
    Jack: I'm getting...
    (lifts up cloak to reveal Jack is looking and sounding more like Aku)
    Jack: ... STRONGER.
  • In an episode called "Samurai vs Ninja" it gets downright hectic and overall a bit eerie since you have two of the most deadliest warriors hunting one another in the art of Shinobi. All the while that they're both cladded for the appropriate elements. One fights in the dark while the other fights in pure blinding light. The whole fight in the very wooden tower is both a respectful mix of Nightmare Fuel and Paranoia Fuel. And to add even more fuel to an already deadly, adrenaline rushing encounter? The soundtrack throughout the whole fight! ... Horror chords and all. Here is the fight in its entirety.
  • Samurai vs Samurai is mostly a goofy episode involving Jack dealing with the Da Samurai, until the last few minutes. Suddenly, an army of Aku's assassinbots from earlier in the episode show up, but these ones Dual Wielding swords and opening the panels in their heads to reveal creepy long faces with razor-sharp teeth. That alone is scary enough, but after Jack finally defeats the entire army, they all combine into what can only be described as the mechanical equivalent of an Eldritch Abomination. Thankfully, it goes down easier than the army did, but it's still freaky to watch.
  • In "The Princess and the Bounty Hunters", a group of bounty hunters team up to capture Jack once and for all by attempting to attack him all at once. Unfortunately, it backfires and Jack defeats them all, with the princess being the only living member of the group. You catch that last line? Jack actually killed living beings, flesh and blood, as opposed to robots and demons. Pretty grim when you think about it.
  • The promo picture for the fifth season shows a much older, war-torn Jack covered in blood.
  • Season 5's trailer shows things truly are at their worst for Jack after all these years. Not only has Aku been putting on the pressure against his evasive foe with new robots and new enemies, but Jack's losing himself after several decades of failure. It's really hammering home that he's just one step away from losing it all, and assuring Aku's total dominance forever.
    • To make matters worse, Aku has destroyed every single time portal, and due to his own travelling to the future, Jack is unable to age. For some, this might seem awesome, but Jack only ever had one goal in mind, and Aku has finally assured that he may never get back to the past, meaning he may be doomed to walk Aku's Bad Future for eternity.
    • The trailer also introduces the Daughters of Aku, who enter into that rare category of 'people who can curbstomp Jack' and make for a particularly vicious gang of assassins. But worse still, unlike the Imakandi or the Guardian, their loyalty to Aku seems pretty ironclad.