Nightmare Fuel / Kero Blaster

• The Negativus Legatia. Described as "pieces of your past that have been cast off", they appear as pure-black blobs capable of possessing living creatures, running machines, and engulfing an entire city. Sasuke mentions having encountered the things before, meaning it's entirely possible that they could appear again...
• At one point, the Negativus Legatia interfere with a teleporter and send Kaeru to a strange train station in an unknown location. The place is full of the creatures, and when Kaeru dies or goes to a shop, Mizutani, Tsubasa, and Sasuke are missing, replaced with color-inverted copies (for the first two) and an unintelligible phone (for Sasuke). The feeling of being in a place totally controlled by the Negativus Legatia, with your faithful friends nowhere to be found, is terrifying.
• The penultimate boss of Normal mode: a possessed Nanao, with an inflated body, bulging eyes, and a crooked smirk on her face.
• Zangyou mode is Lighter and Softer overall, but it has its moments. The penultimate boss looks like the boss (occupation) of OXOX Commerce, but black, with glowing eyes, and what appears to be puppet strings, implied to be controlled by the Work Producing Machine Salesman.
  • Really, the entire plot surrounding the Work Producing Machine in general. It doesn't just make documents that need to be sorted out, it's implied to somehow create clients, a terrifyingly seductive thing for a business down on its luck, like OXOX Commerce was implied to be. The aforementioned corporation's boss is so desperate for business to pay his employees, he ends up in the thrall of the Salesman and takes on any work offered despite his employees begging him to stop piling overtime on them.
  • Stage 6 of Zangyou mode is grayscale and has blood dripping from the ceiling.
• Omake mode's secret areas. Each of them is a Minus World with glitchy buzzes and beeps in place of music, tiles thrown about randomly, glitchy shapes moving about in the background, and occasional dips into cutscene areas. To top it all off, completing each area gives an upgrade for the Kuro Blaster, a weapon which apparently uses Negativus Legatia as ammunition.

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