Nightmare Fuel / StarCraft II: Wings of Liberty

• The mission "Piercing The Shroud" is terrifying. It starts off rather leisurely, with even the stronger zerg units fairly easy to kill, often due to being chained up. Then you cut the power, and the rest of the mission consists of a mad dash for the exit as you try to escape from the invincible Hybrid. If you played the Zeratul Prophecy Mission(s) that has you fight these hybrids with a Protoss army, imagine coming face-to-face with a Hybrid for "real", and you're under equipped to have much hope of killing them.
• The entirety of the Ariel Hanson missions. At first you have to defend the colonists and evacuate them from the zerg. Then, you spend a mission where every night (several minutes in-game) you have to retreat to your base as hundreds of infested terrans bear down on you. And depending on your choice in the final mission, you may see Hanson infested and crawling around the ceiling taunting Raynor to kill her.
• The normally stoic, deadpan and fearless Tosh is clearly wigged out from the Hybrid's psychic "scream" after the raid on the Dominion laboratory. invoked
  Searing. Blinding. Like feeling the sun burning your face with your eyes squeezed shut. I never felt a thing like that before. I hope I never do again.
• Kerrigan's talk with Zeratul in the beginning of "In Hushed Whispers", where she, with an almost childlike glee, extols about how Amon will soon awaken and destroy all life in the galaxy. Her sing-songy voice and giggling make her seem mentally unbalanced and very crazy.
  • Throughout Zeratul's entire mission chain he discovers that Kerrigan is very much not lying about what she said. It ends with him connecting to the Overmind's dead husk on Aiur and seeing for himself the apocalyptic vision the Overmind was trying to prevent by creating Kerrigan in the first place. Because Kerrigan's enemies killed her in this version of events, the Zerg swarm became tools for an even greater threat, The Dark Voice, because she wasn't there to contest his control over them. This allowed the hybrids to control the swarm and unleash their full fury upon the Terrans who were overwhelmed and wiped out. Then, all the Protoss were slowly eliminated as well as they fought a valiant last stand against the Hybrids. Finally, the Hybrids themselves destroyed the Zerg that they controlled and the galaxy falls completely to The Dark Voice.
  • The fact that you can only beat the mission "In Utter Darkness" by losing all your buildings and units after reaching your kill quota. You can slay as many of the Dark Voice's minions as you'd like, but it only delays the inevitable. A subtle touch is the victory screen; there no "Victory!", only "Glorious End!".
• The Moebius Factor has an eerie mood to it, as you're surrounded by Zerg in an over-run city and racing against an invincible Kerrigan to destroy all three data cores before she completes a search of one. This Zerg tune tends to play, enhancing the sense of dread. Even Raynor is unnerved by this encounter, having a heavy drink of whiskey and a recurrent nightmare where he witnesses Kerrigan abandoned to the Zerg on Tarsonis by Mengsk's orders.
• Zerg Creep was already eerie enough before, but now it's a tertiary resource for the Zerg as it significantly boosts their land speed. You'd best have a plan before you send your army onto creep as the Zerg player will have vision on their creep and a Zerg army will most likely be approaching like wild cats.

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