Nightmare Fuel / Pikmin (2001)

• The premise of the game itself. Olimar is stranded on a hostile planet where even the air itself is out to kill him, no-one knows where he is, no-one is coming to save him, and — if he can't repair his ship — his life support will fail, he'll die from an atmosphere (oxygen) that's extremely toxic to him and his species, and worst of all; his family back on Hocotate will never know what happened to him.
• The Emperor Bulblax is the largest enemy in the game by far, and can take the entire day to kill! The Emperor attacks by tongue lashing your Pikmin, jumping on them, and roaring at them to startle them. When half his health is gone, he will do this gigantic jump where he flies off the screen and then slams back down!
  • Its home, the Final Trial, has rather unnerving music due to the creepy intro then leading to an uncomfortable happy sounding tune with some creepy bits sneaking in, as if the song is trying to hide something. This Youtube comment sums it up perfectly:
  This song is the musical manifestation of a brave child whistling to himself to ward away the mad and howling dark.
  • Emperor Bulblax's theme. It's a very menacing Ominous Pipe Organ that sounds similar to Super Mario 64's Final Boss theme.
• The Smoky Progg. Oh jeez, the Smoky Progg. A nearly unstoppable demon frog made of smoke (that leaves a trail of the same noxious smoke wherever it goes), who, upon hatching, makes a beeline for your Onions and tears your Pikmin out of the earth to disembowel them. That, and it's implied to be a larva of the already creepy Mamuta which has been mutated (and apparently pissed off) by you disturbing its egg. Its anatomy is perplexing to the point of it resembling a Eldritch Abomination, and upon dying, the entire thing melts, leaving nothing but a small pearl.
• In the Forest Navel, your ship's parts locator points you in the direction of a certain cave. After noticing there doesn't appear to be anything there you go in only for the Beady Long-Legs to drop from the ceiling and begin stomping around in an attempt to squash your pikmin. The music turns ominous, the pikmin can't be controlled by the c-stick because they'll try to attacks the legs which are the main weapon and can end up with your pikmin getting flattened.
• The non-canon Bad Ending is surprisingly dark and disturbing. Olimar's life support system fails, his Dolphin ship — the one thing that could let him escape — crashes again and is destroyed beyond repair from Olimar attempting to blast off to Space with it only partially-repaired in desperation, and he perishes on the planet; so the Pikmin recover his body, take it back to an Onion, and Olimar is turned into a Pikmin himself. Not to mention it's implied that they're not strong enough to pull him out. If you remember that Pikmin that are left in the ground bloom into a flower and shrivel up back into a single leaf, it's not hard to imagine Olimar's ultimate fate is.
  • Thankfully though, Pikmin 4 follows this up, Olimar is freed from his mutation and goes back to his planet and family.
  • The final day results screen music can be this. It plays for all three endings (good, neutral, and bad) and has a rather creepy instrumental with a tone that is ambiguously between success and failure. It's possible that your first exposure to this track will be between Olimar's second ship crash and him turning into a Pikmin, and you can associate this track with the bad ending instead.
• The Puffstool. You're walking along in the gloomy Forest Navel, when suddenly this bugger pops up. Right then, let's just attack it like any other enemy. Wait, what the-? Spores? OH GOSH, my Pikmin now have these creepy-ass mushroom caps instead of flowers, and they're attacking Olimar! Mushroom Pikmin in general are incredibly creepy. They lose all facial features besides their eyes, which become white and soulless, with no pupils to be seen. On top of that, they admit a creepy, almost child-like giggle when walking around the Puffstool, and when attacking Olimar, they sound almost gleeful to be doing so. This can't but make one wonder if it's the effects of the spores, or if the Pikmin have darker feelings towards Olimar than what they express...
• The Nova Blaster part from the first game. "What could you possibly mean," you ask? Simple enough. That thing is capable of piercing through and destroying stars. It's a doomsday device. And it's only about the size of a baked bean can. Sweet dreams.
• The Geiger Counter, a required part to complete the game, according to Olimar, is always letting off spontaneous clicks and buzzes. While some Background radiation is completely normal (since Distant Planet is based on Earth), the spontaneous nature of the Counter going off isn't. It's implied Distant Planet has strong and constant radiation, making it harmful to Olimar.
• The bottomless pits in the Forest Navel. Aside from the sheer darkness, you can only see mushrooms. If your Pikmin fall down there, they'll die. Plus, there's a chance that the Libra can accidentally bounce into said pits and disappear, ruining your chances of escaping the planet.
• Olimar's voyage logs can be surprisingly dark as he muses about his life back on Hocotate and the situation he's in. If you decide to continually go to sunset and never leave the Impact Site, however, Olimar will slowly start going insane in his entries, describing hearing voices inside his head, angrily ranting about his family and boss, and considering the thought of being a Pikmin to escape his everyday life. It's rather disturbing, as it's clear that spending several weeks stranded is clearly taking a mental toll on Olimar, and he gets progressively more unhinged the longer you take. And in the Japanese version and some other translations, he eventually loses all energy and only complains about how tired he is, in one eeringly short sentence with red text.

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