Nightmare Fuel / Fate/Zero Paradox

• Rider X. Just Rider X, full fucking stop. To start with, he’s Megatron, straight out of the Transformers Prime continuity, and he’s just as dangerous here as he was there. From the outset, it becomes clear to the audience that he’s scarily good at manipulating others, from convincing Tokiomi he’s just an arrogant brute to aiding Kirei’s descent into darkness. Then at the Banquet of Heroic Ideals, he straight up tells the other Servants what he intends to do with the Holy Grail: Drink down every last drop of its power and use it to begin a conquest of every universe he can find, starting with the Fate Universe and his own.
  • Dark Energon. Just Dark Energon. An evil energy source that comes directly from Unicron's blood, an analogous figure to Satan for Cybertronians. It's disgustingly versatile and will corrupt anything it touches...including the dead, as Iskandar found out the hard way. Servants are also not safe from this: Iskandar is nearly corrupted, and the final faces of Hundred Faces become Megatron's slaves once he infects some of them. Also, consider that KIREI was infected by this...
• Berserker X's first appearance to the other Masters is enough to give loads of material. His mere presence without the eyepatch seal is enough to make the figures witnessing to have visions of painful and bloody deaths. Even the more battle-ready Masters are heavily affected by the visions!
  • Scratch that, Berserker X itself is Nightmare Fuel despite being a good guy. He's leaps and bounds the most powerful X Servant regarding to raw power, it's actively looking to fight anyone, can take humongous damage before even starting to twitch, and, the scariest part? This is Kenpachi Zaraki at his WEAKEST.
  • To further amp the fear factor, he's the one X Servant that actually makes Gilgamesh fight seriously. "How seriously?" you may ask. Enough that he saw fit to finish the fight with Ea... and Kenpachi survives a direct hit. He dies soon afterward, sure, but think about it: through all the Nasuverse, in all the canon instances Gil pulled Ea in a fight, the only time people lived was when they bailed out before the attack, had a conceptual defense in the level of Avalon, or was a Beast of Humanity. And, remember, this is Kenpachi at his weakest. If he was summoned as he was in the Thousand Year Blood War, there was a non-zero possibility of him continuing fighting after a blow of that level or at least killing Gilgamesh at the same time. Let that sink in.
• Let us not forget Zero's local sources of Nightmare Fuel, Gilles, and Zouken. While Gilles doesn't do things much differently than in canon, here, as Zouken becomes his Master after Ryuunosuke is killed, he manages to get some tidbits of information from Prelati's Spellbook that allow him to improve his familiars into absolute nightmares that seem almost out of Resident Evil.
• Tokiomi and Jade's ultimate demise. Tokiomi wanted to try and speak with his disciple to clarify what was happening, only to be backstabbed with extreme prejudice and infected by the aforementioned Dark Energon. Then, Megatron orders Jade to attack Team Kariya, losing control of her body, and when that fails, to kill herself, all wondering why her Master she trusted for so long would suddenly order her like that. Even when Diarmuid escapes suffering, a Lancer Servant still has to suffer in his place!
• This iteration of the talk between Angra Mainyu and Kiritsugu somehow surpasses the original in psychological horror. Throughout the story, Kiritsugu has become ever so slightly more like a true hero than a killing machine but still holds true to his ideal of "kill one to save many". When put through the ship test like in canon, he soon realizes where this is going, yet is forced to go through it as he slays people after people, ending in killing Kakashi after he protects the illusionary Shirley. It's more disturbing than even the canon interaction because Kiritsugu has been warned by others many times of what would be the end of his ideals through the story, and now he can only watch horrified as he slays even those he once cared for. And then you add the emotional baggage of being partially responsible for the Fuyuki Fire, and it's a wonder he didn't become a completely empty shell of a man.
• Fuyuki City gets put through all sorts of scary things throughout the war.
  • Picture this: you are walking through streets at night, living your life, when suddenly something happens. You hear the sounds of gunfire, metal against metal, you see things you can't quite understand, like many figures in power armor fighting against weird cosplayers with awfully realistic weapons. And you heard the explosions. Explosions throughout the city, as if were under attack by an army. This is what Tex's attack would look like to an outsider.
    • If you think about it had Tex not been driven insane by that point & been less focused on grandstanding she could have easily modified the explosives & timers, while having her copies rely on stealth to hit all her targets simultaneously before the Fuyuki Hotel had even finished crumbling.
  • And this in addition to the canonical incidents of the Gigantic Horror and the Fuyuki Fire. Three big tragedies in the space of two weeks, and that's without accounting for the serial killer roaming the streets and the destruction of many parts of the city in sudden fashion. Nothing Is Scarier, indeed.

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