[[quoteright:320:https://static.tvtropes.org/pmwiki/pub/images/divermons_true_form.jpg]]
[[caption-width-right:320:Oh, Hikari, we need your... ''"help"''.]]
* In episode 10, the Digimon Emperor manages to take control of Agumon using a Dark Spiral, which is much more powerful than the Dark Rings.
--> '''Digimon Emperor:''' So, you've come back to me, Agumon. And I've got a new friendship bracelet for you! ''[Throws the Dark Spiral onto Agumon's arm]''\\
'''Agumon:''' [[OhCrap What is this?]] ''[Grunts in pain as the Dark Spiral takes effect]''\\
'''Digimon Emperor:''' You are mine again!\\
''[Agumon's [[RedEyesTakeWarning eyes turn red]] and he growls]''
** And then the Digimon Emperor makes him digivolve into [[SuperpoweredEvilSide MetalGreymon (Virus)]], who looks [[https://vignette.wikia.nocookie.net/villains/images/5/5c/MetalGreymon_Virus.jpg/revision/latest?cb=20190103023235 absolutely terrifying]].
** Compounding this form's horror value even further, [=MetalGreymon=] (Virus) (which, keep in mind, is the ''original'' design for [=MetalGreymon=]) is what happens when a Greymon tries to cheat death and extend its vital functions through remodeling. However, their flesh is unable to hold out, turning a sickly blue and making the Digimon look more like a zombie. Considering that Agumon was able to reach the ''perfected'' [=MetalGreymon=] form, and is now forced into the MechanicalMonster that is this version, imagine how much pain Agumon is going through due to the possible draining of his vital functions, ''[[AndIMustScream even as he's being controlled by a Dark Spiral.]]'' Compared to that, [[TheBerserker SkullGreymon]] sounds like a walk through a field of daisies, doesn't it?
* The Dark Ocean, and the creatures living in it.
** The Scubamon, or rather the unidentified things that were ''pretending to be Scubamon'', in episode 13 who live near the Dark Ocean want Kari to have a child with them. One of them even calls Kari a "virgin". And no, [[RapeIsASpecialKindOfEvil they don't seem to care much for her consent.]] It's only slightly better in the dub where they want to brainwash her into being their "Queen" so she can lead them to greater evil heights. While the exact details are unknown here, ''Anime/DigimonGhostGame'' implies that they were humans converted into Deep Ones.
** It's also implied that they want her to bear their children so they'll have the power to take on the master of the Dark Ocean, a twisted and powerful creature called Dragomon [[NothingIsScarier who never physically appears in the series]] and is the Digimon equivalent of ''Cthulu.''
*** Worse is that if Dagomon's episode in ''Digimon Ghost Game'' is to be taken at face value, then the Dagomon is pretty much real and the giant thing is actually an illusion, and it converted a bunch of people to become his servants. The fear of what will happen to Hikari if she gets captured suddenly becomes real.
* During episode 20, Ken starts hearing voices that laugh at him. He even has a vision of himself about to fall into a deep dark hole. Instead of taking a moment to stop and consider what's going on, Ken instead grows more and more maniacal.
** It's also implied during to his jaunt into the Dark Whirlpool to gather Devimon's loose data that ''[[NothingIsScarier something]]'' followed him back.
* The apparition of Devimon.
** His appearance in the Dark Whirlpool is a [[http://vignette2.wikia.nocookie.net/digimon/images/1/15/List_of_Digimon_Adventure_02_episodes_19.jpg/revision/latest?cb=20100410222248 fragment of his former self]] who the Digimon Emperor hunts down to gather his data to create Kimeramon. The implication of Devimon being here is that either he's been reviving all this time, or that ''he's spent three whole years alive and reforming after Angemon beat him.'' And then when his data is used to complete Kimeramon his personality turns out to have survived and his evil influence turns Kimeramon into an unstoppable rampaging berserker that takes Magnamon, a Royal Knight with power on par with a Mega Level digimon, to finally be put down. Even three years later, the original BigBad of Digimon is still terrifying.
** The only other implication is no better: the Dark Whirlpool could be a link between the Digital World and the Dark Ocean, where extremely evil Digimon are implied to be sent when they die. The voice is implied to either be Devimon's spirit taunting him or something else entirely. When the hole opens he sees something the viewer can't and screams in horror until it closes, at which point he goes LaughingMad. Either he saw the spirit of an evil Digimon like Devimon or Apocalymon in there... ...or he saw the otherwise absent ''Dragomon'' and like a character in the Cthulu Mythos went mad from the sight of him.
* The Digimon Emperor's VillainousBreakdown after realizing the Digital World wasn't a game.
--> '''Digimon Emperor''': [[HeelRealization I had no idea...]] [[MyGodWhatHaveIDone What have I done?]] I thought my Dark Rings were a stroke of genius. I never realized I was causing pain. I made them work for me tirelessly, without ever giving them a break, and I was cruel to them beyond imagination! I'm a monster! I can't believe what I've done?!
* The creepy email to young Ken in "Genesis of Evil", actually sent by Oikawa. Not only the episode's tone is just haunting, the whole story sound completely straight of a creepypasta.
--> "I'm sorry for the loss of your brother. It must have been hard to take, but don't worry. Your brother is in a better place than this world. He is finally at rest. But when his soul became free, yours became trapped. You will now bare the burden of both his destiny and your own. Now that your parents have lost their hopes for their "perfect child". You will be expected to carry out the dreams that Sam can no longer fulfill. This world will become unbearable for you, the pressure to succeed will be too great. But let me tell you about another world that is much more appropriate... a world where your soul can finally be free, where you answer to no one but yourself."
** From the same episode, young Ken's first trip to the Dark Ocean. He finds himself standing at the edge of the water. Then the audience is treated to bits of dialogue of Ken as the Digimon Emperor as Ken gives in to his anger and places his Digivice in the water, letting the Dark Ocean corrupt it.
** His first trip to the Digi-World, from the same episode, is apparently innocent but still unsettling. He is walking through an inhospitable desert along with Wormmon and an unknown Ryo Akiyama, and out of the blue a Gazimon somehow bursts out from the sand and lunges towards Ken, who becomes scared like the little boy he is. Fortunately, Wormmon is here to shield Ken and knock out the Gazimon in a saving dive, but he still tells Ken that while he is happy his human partner is a kind boy, Ken ''needs'' to become strong to survive...
** However, the worst of his travels in the Digi-World is shown later, in episode 43, when another dream shows Ken's and Ryo's victory over Millenniummon. Suddenly, we witness the death throes of a creepy giant digimon we have never seen before, which collapses in what appears to be the same desert, sticking out its tongue and striking a chilling lost stare from its dragon eyes. Its body is almost indistinguishable in the distance, but we can see an eerie yellow aura and a pair of Machinedramon cannons strangely mounted on its back before the monster disappears - all while Ken and Ryo are standing in a strange wind that brings ''blood''-colored particles around them. And then the Dark Spores come out, darting towards Ryo, only for Ken to tackle him out of the way and receive the spores on his own neck. Only because we later learn that the spores were real we can know this sequence was not a honest-to-god nightmare.
* Arukenimon appearing in Ken's room in the middle of the night in "If I Had a Tail Hammer".
* The end battle of episode 28, where Stingmon pulls a full Nelson on Exveemon while Digmon tortures the latter with his ''drills''. Even worse given that he sometimes nails his drills in Exveemon's ''[[GroinAttack groin]]''.
* The encounter T.K.'s mom has with Oikawa. A strange, pale man just confronts you in the street and ominously hints that the life threatening events that nearly killed your sons are happening again, before disappearing?
-->'''Oikawa:''' Enjoy the holidays, ma'am. It's the most ''wonderful'' time of the year...\\
'''Natsuko:''' ''(Thinking)'' He's gone! What have the boys gotten themselves into this time? I thought this Digital World stuff was over with, now the danger starts again!
* Arukenimon and Mummymon abducting children to implant with Dark Spores. And [[CreepyChild the children]] themselves, even before getting the Dark Spores.
** What makes it worse is the build-up; right after some light-hearted action with the Children, we cut back to a playground in Japan; a lone child is sitting on the swings, and when we cut in for a closer shot, ''Mummymon is there too.''
-->'''Child:''' Oh, hey, mister. Guess you're all alone too. You wanna be friends?\\
'''Mummymon:''' ...''(SlasherSmile)''
* Daemon's entire appearance. He's not only a mysterious being with enormous amounts of power whose very presence gives off a creepy Satanic vibe and who leads a trio of frighteningly powerful devil Digimons, he's also a villain who comes literally out of nowhere - as in suddenly levitating out of a portal in midst of the street! And while Arukenimon, Mummymon and Oikawa had proven by this point that even at their goofiest they were still powerful enemies with very evil intentions, Daemon is even worse, because he is completely unrelated to them and he is definitely ''not'' goofy. He is at least just as dangerous, but unlike them, we know ''nothing'' about it.
--> '''Daemon:''' The powers of darkness are not to be trifled with!
** The fact that at the end of the battle, Daemon was just be sealed away rather than defeated. Not even Imperialdramon Fighter Mode could do more than ''contain'' him, and Daemon still made it look like he was taking it easy.
* Oikawa's hallucinations in the cemetery in "[=BlackWarGreymon's Destiny=]".
* [=MaloMyotismon=] torture-murdering [[AlasPoorVillain Arukenimon and Mummymon]].
** The way it happens to Arukenimon is particularly bad, considering how drawn out and brutal it is. Not to mention that many have noted it [[DoesThisRemindYouOfAnything vaguely resembles]] something else [[RapeIsASpecialKindOfEvil entirely...]]
-->'''[=MaloMyotismon=]:''' What should I do next? Show me what you fear!\\
'''Arukenimon:''' No! Please! ''[[AnythingButThat NOT THAT!]]''
** His design is a bit creepy as well, especially his shoulder cannons that open like organic jaws.
* The completely surreal final battle against Cherubimon in ''Hurricane Touchdown/Supreme Evolution! The Golden Digimentals''.
** Kokomon's evolution line in this continuity is this as a whole. While in the dub the Dark Digivolutions are a result of the same virus that created Diaboromon, [[NothingIsScarier the Japanese version leaves it ambiguous as to what corrupted him]]. While corrupted, Kokomon is nothing short of a PsychopathicManchild, its childlike, playful nature becoming corrupted into something far more malicious. It's also a SuperPersistentPredator, hunting down any child with a regular Digivice under the assumption that they're Wallace/Willis. On top of ''all'' of that, it's a deceptively powerful RealityWarper; Wendigomon alone is capable of creating pocket dimensions, which it traps the older [=DigiDestined=] in and can revert anyone and anything to how they were seven years ago. This is even present in the Digimon's official Reference Book bio, so it's something that any member of its species can do. As Cherubimon, it evokes the look of a MonsterClown and proceeds to do this with the younger children, [[WouldHurtAChild continuing to show no restraint during the fight and tossing the Digimon around even when they're reverted to the In-Training level]]. Kari notices early on that Wendigomon is [[TragicMonster crying on the inside]]; however, by the time it becomes Cherubimon, she notes that the crying monster is gone. [[TheMindIsAPlaythingOfTheBody The source of its corruption has completely taken over]] and poor Kokomon has to be put down [[DyingAsYourself just so it can feel happiness again]]. Yikes...
* Diaboromon's return in ''Revenge of Diaboromon'' shows that the virus Digimon is just as dangerous as he was in ''Our War Game'', staying one step ahead of the Digidestined and achieving his goal of materializing in the real world as [[EldritchAbomination Armageddemon]], handily beating Omnimon ''and'' Imperialdramon.
* In the English dub at least, the fake Blossomon in the episode where Silphymon debuts. Not only is it bigger than usual, but unlike the other Black Tower-created Digimon, this Blossomon never talks or even makes human-created grunts. Instead, it roars [[HellisthatNoise a nightmarish roar]]. Even In-Universe, this roar actually traumatizes Kari out of digivolving Gatomon to Angewoman, just as she's about to.
* What the Digimon Emperor does with the Dark Rings. Even the GagDub stops with Digimon being painfully struck by the things.
** The opening of one episode, where Ken chases an Elecmon with a Tuskmon, beats it with a whip until it can't stand, then throws it into a jail cell to fight another Elecmon.
** And then again with two Gotsumon. A third Gotsumon manages to run away, and has to watch the two fighting, implicitly to the death.
* Ken's reunion with Leafmon in the Village of Beginnings reminds us of [[WhoWantsToLiveForever the downside]] to Digimon's standard BornAgainImmortality--Ken encounters some baby Digimon there who recognize him as ''their killer'' and are somewhat justifiably pissed. Not to mention that this scene confirms that, whether directly or indirectly, Ken definitely did ''kill'' Digimon while he was the Digimon Emperor.
* From episode 49, Ken's disturbing and [[TearJerker heartbreaking]] vision within his "[[LotusEaterMachine happy place]]" of himself as the Digimon Emperor being attacked by several angry Digimon. Followed up by a vision of his late brother Sam, telling him to give up and embrace the illusion.
--> '''Ken''': Huh? Wait a sec, Sam! I thought you were dead!
--> '''"Sam"''': I've come back to invite you to stay with me here, where you no longer have to suffer for the errors of your past. I'm your brother. Trust me.
--> '''Ken''': I can't keep these visions out of my head. If I stay, will you help me? Where have you been? I've missed you, Sam.
--> '''Wormmon''': Ken, can you hear me?
--> '''Ken''': Huh? (''Ken turns to look at Wormmon, when he turns to look at "Sam" again, "Sam's" vanished'') Wormmon, what happened to Sam?
--> '''Wormmon''': He was never really here.
--> '''Ken''': (''breaking down'') But he promised to help me!