This is based on opinion. Please don't list it on a work's trope example list.
Nightmare Fuel / Receiver of Many
Receiver of Many
Say that youíre a single mother living in a deeply patriarchal society where women are controlled by the men in their lives. Youíre pretty much pressured into betrothing your daughter to a man twice her age while she was still in the womb. After being abandoned by your baby daddy and finding out that your daughterís fiancee lives isolated from the rest of the world, youíre faced with the possibility of never seeing her again. Then, years later you discover that youíre daughter has been kidnapped by her fiancee with her fatherís permission. You donít see her for two months and you have absolutely no idea whatís happening to her. Thatís everything that is going through Demeterís head. Adult Fear at its finest.
Almost averted with the fact that Demeter wasn't pressured into the betrothal and people were constantly telling her that her daughter was completely safe. Not only that but Hades later told Demeter that she had full permission to see her daughter whenever she pleased because he doesn't follow the principles of what mortals do with marriage. Also when Persephone returns to the Upperworld, Demeter ups her My Beloved Smother tendencies and later she goes out of her way to completely attempt to sabotage her daughter's marriage to the point that it leads to Hades' being drugged and almost raped by Minthe. All this leads to Persephone Calling the Old Man Out and declaring that if she (Demeter) ever tries to interfere again, she'll never see her (Persephone) again because the seasonal deal doesn't mention that she must be with her mother during the summer months.
When Minthe goes to make an ally of her father Kokytos on Demeterís orders. He convinces her to stay until the famine ends, then he pretty much sells her to the men of his court. And right in the middle of an orgy between a bunch of nymphs, humans and satyrs, she gets drugged and raped by one of the satyrs.
Kokytos isnít exactly harboring and feeding the mortals in his court out of the kindness of his heartÖ heís keeping them as a food source for his people in case the famine doesnít let up.
The Keres. Spirits of violent death and bloodshed that even Hades, one of the most powerful gods in the cosmos, is wary of. When weíre first introduced to one, it turns itís head all the way around. Creepy.
Everything Merope has been through:
Being drugged, incapacitated, and burned alive by your own husband definitely qualifies as nightmare fuel.
And as if he didnít make her suffer enough, Sisyphus placed a glamor on Merope to trick the hosts of the underworld into sending her to Tartarus in his place. No matter how desperately she tried to assure everyone that she wasn't Sisyphus, no one believed her.
After spending a month in the Pit, the trauma Merope suffered was so bad that Hypnos had sedate her to stop her from screaming. And even in her comatose state she couldnít stop shaking.
Everything about Tartarus. Itís pretty much where nightmares are born.
It's so dark down there that the light is actually drained from anything that enters it.
On each side of the path leading into Tartarus, thereís a bottomless pit that no one can escape from. Falling down there is the closest thing to death for a god.
The Hekatonkheires. As their name suggests, they have one hundred hands on each arm and fifty heads. And they have the ability to subdue gods. And there's three of them. Think about that.
The Fields of Punishment are used for sinners the gods wanted to make examples of. The kicker? All the punishments they suffer are in their heads. Their minds are the real prison.
The vision Kronos shows Aidon and Persephone in Tartarus. It starts out fine and dandy with Hades and Persephone ruling over the heavens and expecting a child...then Persephone sees Hadesí face morph into Kronosí and it all goes downhill from there.
Persephone watches as a fifty foot tall Kronos terrorizes Hellas and devours all the gods, including her mother.
Then the vision shifts to Persephone being raped by Kronos and Aidon being forced to watch while chained to a rock with an eagle eats his insides.
The worst part is if Demeter doesnít put an end to Winter and balance isnít restored to the cosmos, thereís a very real possibility that everything from Kronosí vision could happen.
Since receiving the underworld, Aidoneus has been hearing Kronosí voice trying to tempt him to start an apocalypse. Then there's the fact that Kronos can eavesdrop on Aidonís private thoughts and use them against him...
Destroyer of Light
While heís escaping the underworld, Sisyphus uses the Chains of Tartarus to injure Thanatos. The chains were woven into his flesh and Aidon had to break both of his arms to get him free.
When that scene happens in the book, while Thanatos is acting all fine and dandy and telling Hades to get it over with, he (Thanatos) looks at Persephone and she can see that it's an act because she can see how terrified he really is.
Sisyphus exploiting Winter by stealing whatís left of the earthís fertility, weakening the gods in the process and throwing the cosmos further out of balance. Eventually, he manages to accumulate enough power to possibly destroy the gods.
Minthe drugged Hades with ergot (And by Minthe's own admission, the amount she used would be a lethal amount for a mortal) and if it wasn't for his mental link with Persephone, he would've been RAPED!
Doubles as awesome, but the scene where Persephone pulls Sisyphus from the ether, breaks his legs, summons the Keres and the Hekatoncheires, and sends him straight to Tartarus. By the time sheís done with him, Sisyphus goes from being the hubristic sorcerer king of Ephyra to a groveling, sniveling mess. Ares was visibly shaking by the end of it.