Nightmare Fuel / Guardians of the Galaxy

Rancor is so happy to see you.

• Wolverine's ravenously psychotic great-great-great granddaughter from volume 1, Rancor, is a walking repository for these moments. If her Ax-Crazy behavior wasn't enough to unsettle (she scalps her own cousin—non-lethally—just to remind him who's in charge) her constant, horrifying smiles will. Some of the best artwork in the 90s series was of Rancor and her various nightmare expressions.
• The opening of issue 7 in Volume 2, beginning with the original Guardians fighting the Badoon invasion of Earth, only for them to randomly start dying, due to time itself falling apart at the seams.
• The Eldritch Abomination the team are attacked by on a mission to a Dyson Sphere. Only it's not an Eldritch Abomination. It's the sphere's population, who were the ground zero for a Negative Space Wedgie that fused them into one big screaming mass, which devours everything it touches. And nothing the team has can kill them.
• Moondragon getting "impregnated" by an Eldritch Abomination, as well as how it got into her, by forcing its way down her throat. The only consolation is that we don't hear the noises, which the rest of the Guardians assuredly do.
• What a just revived Thanos does to the Chuch's homeworld. He razes it to the ground and kills every living thing on its in the space of a few hours, all while in a blinding rage.
• Groot◊, possessed by the gone-rogue Venom symbiote. Later, Rocket◊. And then, Drax◊.
• The final fate of the universe in Infinity Wars. Gamora takes a page of her father's playbook by making half the universe's population dissapear. But while Thanos was merciful enough to simply just have them vanish form existence without pain or any kind of suffering, Gamora took the insanity to sadistic, and incredibly terrifying levels by having every single individual in the universe fuse with another to form a new being. And yeah, at some point it is implied that the two old beings are still conscious inside the new merged being, making it a horrifying case of Silent Scream.

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