Please don't list this on a work's page as a trope. Examples can go on the work's YMMV tab.
Nightmare Fuel: Super Mario Bros. Z
Admit it, the scenes where Mecha Sonic murders Sonic's friends and him gazing at the destroyed Yoshi's Island made you cringe.
Episode 8 has a lovely scene where the viewer is treated to a closeup of a dying Rouge. Eeeep.
Hell, any scene that has to do with the events on Mobius could qualify, since they almost always involve graphic destruction and even more graphic death.
The end of Episode 8, made such with that damn Cliffhanger.
Minus World is historically referred to by the simple, cold moniker of "World 36" and is revealed to be a pocket dimension from which there is no escape. During an ancient war between the Mushroom Kingdom and the Koopas, it was used as a method of execution by both sides, who would throw their prisoners down the warp pipe to starve to death; their corpses, as well as those of anyone unfortunate enough to stumble inside, litter the ground of the zone.