Nightmare Fuel / Zork

• In Zork I, if you complete the exorcism task in the Entrance to Hades but then end up getting killed later on, instead of you getting recalled to the Forest Path, your spirit gets recalled somewhere else:
  As you take your last breath, you feel relieved of your burdens. The feeling passes as you find yourself before the gates of Hell, where the spirits jeer at you and deny you entry. Your senses are disturbed. The objects in the dungeon appear indistinct, bleached of color, even unreal.
• The Grues. Darkness dwelling, man-eating creatures that are scared of light. What happens if you wander into a pitch black area with no light source? "It is pitch black. You are likely to be eaten by a Grue."
• The aforementioned Human Sacrifice ritual in Zork III, with an Early-Bird Cameo of the Black Cloaked figure, a.k.a. the Big Bad Krill from Enchanter. We'll let the narration text speak for itself:
  This is the interior of a huge temple of primitive construction. A few flickering torches cast a sallow illumination over the altar, which, atop a row of stairs, is still drenched with the blood of human sacrifice. Behind the altar is an enormous statue of a demon which seems to reach towards you with dripping fangs and razor sharp talons. A low noise begins behind you, and you turn to see hundreds of hunched and hairy shapes. A guttural chant issues from their throats. Near you stands a figure draped in a robe of deepest black, brandishing a huge sword. The chant grows louder as the robed figure approaches the altar. The large figure spots you and approaches menacingly. He reaches into his cloak and pulls out a great, glowing dagger. He pulls you onto the altar, and with a murmur of approval from the throng, he slices you neatly across your abdomen.

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