Nightmare Fuel / Enter the Gungeon

• The Gungeon itself is an Eldritch Location to the umpteenth degree. It exists outside the boundaries of regular space-time and the interior constantly transforms of its own volition, so it's nearly impossible to be accurately mapped. And once a Gungeoneer enters, they can't leave until they kill their past. And as of the start of the game, many gungeoneers, most notably Manny and Blockner have never been able to leave.
  • Even worse, the Gun Cultist enemies reveal the final fate of many gungeoneers; having completely given up on changing the past, they choose to fight alongside the same Gundead they once fought against.
• And then there are pasts themselves. While most examples are not as bad, there are a couple that will allow you understand why they want to change it so badly.
  • Marine was a low rank Primerdyne soldier who was present at the dimension travel experimentation facility when an experiment went wrong and summoned a monstrous thing that killed a lot of his men while he fled in one of escape pods. Said entity that we meet as his final boss, Interdimensional Horror, gives a good idea why: an inexplicable alien Eldritch Abomination with fleshy tendrils, hollow eye sockets, his own army of absolutely demonic minions that shoot fire and even Reality Warper powers as he seems to be capable of transporting bits of his own dimension into this one for a short time. And then it's flesh disappates as it dies, leaving behind only skull. The thing was so powerful that, had Marine intervened back then, he would have died, even moreso than his more experienced comrades who met this fate and it took marine getting what's a essentially almost a lifetime of training in Gungeon to finally beat that thing.
  • Hunter was a treasure hunter of sorts, hunting down a strange sword-like artifact, but was traced by Nazi By Any Other Name who stole the artifact for malicious purposes. She traced them to a manor of her nemesis, Dr. Wolfenclaw, who trapped her for experimentation, but then froze her for over 1000 years, explaining why her sidearm looks new if a bit rusty. And the worst is, she got separated from her pet wolf, meaning she was a lone, frozen for a long time and would be absolutely shocked when unfrozen. No wonder she seeks to prevent that from happening in the first place.
    • Even in the timeline where she does succeed, she only does so by using blanks, something she had no way of having back in the first timeline. And even then, Dr. Wolf still sics his Monster on her, an absolutely horrific electricity-hurtling Frankenstein Monster expy.
  • The secret Gungeoneer, the Robot, has what's possibly the scariest past: He is not trying to Set Right What Once Went Wrong: he is doing the inverse. Back in his past, his planet was a stage for an uprising of robotic regime, where he was the most dangerous and cruel fighter responsible for hunting down members of La Résistance, to the point the EMP-R 0 R himself recognizes him as one. One day, a leader of resistance was caught and brought to arena for a fight with Robot, but he rejected the program and fled to Gungeon, where only his head remained. After he gets his hands on the time travelling device that is the Gun, he uses an opportunity to kill the last human. Satisfied with the outcome, EMP-R 0 R declares their directive fulfilled and all robots, including playable, shut down, leaving behind a barren planet. Roll the credits.
    • As a reminder, all of this is conducted by a Tv Head Robot with a smiley face and numbers as eyes who frequently falls flat on his face and makes cute beeps. Beware the Silly Ones at it's finest.
    • Thanks to the nature of the Gungeon, he still returns to it functioning even after supposedly shutting down in a new timeline. There is an absolutely murderous killer machine still remaining along the Gungeoneers to indulge in its killer programming and they don't know about this.
• Let's say you've beaten all of the main four character's pasts, but decide to replay a character's past. You make your way to the final chamber, walk up the final flight of stairs to get to the Gun That Can Kill The Past... and then a giant goddamn skeletal hand bursts through the floor and drags you to hell. Welcome to The Very Definitely Final Dungeon, Bullet Hell. Have fun.
  • A surprise to no one, the location itself. An absolutely horrific iteration of Hell, where fiery landscapes alternate with a horrific Creepy Cathedral that has creepy stone carvings with eyes, hands and faces, horrific flaming skeletons strung along the walls and tons and tons of pits filled with what seems to be darkness itself, with tons of various Bullet Kin resurfacing and sinking, screaming in constant agony.
  • The unique denizens found only here further drive the dreadful atmosphere. Fallen Bullet Kin are horrific demons with Slasher Smile, a flame-throwing pitchfork and deeper voices that revel in misery and suffering of Gungeoneers and their own kind; Shotgrubs are a cross between a demonic grub and Shotgun Kin that sport creepy red eyes and wield literal Weaponized Brethren as their shotguns that attack more chaotic than every other type; Kreeches further twist the parody of Shotgun Kin, scurrying around on four legs and occasionally opening their fake shell to reveal a ton of eyes that it then fires out; Flesh Cubes, invulnerable cubes of metal with flesh from the faces of living beings strung along them; And finally, Tombstoners, living tombstones that shoot out crosses of bullets and act as a Praetorian Guard for the True Final Boss.
  • And as absolutely terrifying cherry on top, there's the True Final Boss himself:The Lich. He starts off as a skeleton with bullets for eyeballs in a trench coat and fedora. Nothing too freaky so far... until you deplete his health the first time, revealing that (in a first for the game) he's a Sequential Boss. How does the game reveal this? By having the same skeletal hand that dragged you to Bullet Hell tear through the floor and drag you to the second arena, where the Lich has turned into a massive frickin' skeleton. And if that wasn't enough, his third phase looks like a mix between Shelleton and Revolvenant, you fight him on a platform that seems to be floating in the void and his patterns give the true meaning to Bullet Hell.
• The entirety of the Oubliette is absolutely horrific. A disease-ridden pit sealed off from the rest of the Gungeon, filled with horrifically mutated bullet kin, all set to a backdrop of filth-covered metal walls and pools of green goop. Worst of all, there are bullet kin dotted around the rooms, lying on the floor and writhing in pain with their faces warped by agony. Walking through these diseased bullet kin turns them to dust, You Bastard!... or maybe not.
• It's not readily apparent considering the relatively cutesy art style of the game, but some of the enemies you're fighting are seriously creepy. Shroomers have the top of their head open and there's nothing inside, and fall apart in pieces when they die, Creeches are monsters mimicking Shotgun Kin, if Shotgun Kin walked on four arachnid legs and opened up to reveal a ton of eyes used as projectiles, The Agonizer is the essence of fallen Gungeoneers made manifest and screeches with each attack... the list goes on.
• The Eyeball Room. Using a specific active item (the Teleporter Prototype) has a very, *very* slim chance to teleport you there. What is it? A big empty room with a static giant eyeball in the middle. What's it for? That's a very good question, and no one seems to really know. Fan consensus for a while was that it was related to the free "Supply Drop" update/mini-expansion, but as of the time of this writing, that is out, and the mystery is no closer to being solved. Oh, and to make things weirder, going here unlocks an item (the Yellow Chamber) which is normally unlocked via a completely different and unrelated method. Weird, ainnit?
• Speaking of which, the Yellow Chamber counts, though that should hardly be a surprise given its namesake. One of its many benefits is that it randomly charms an enemy to fight for you for the duration of the room. If the charmed enemy is the only one left in the room, it disposes of them. How? By having a cluster of tentacles suddenly emerge from the ground under them and crush them with a Sickening "Crunch!".
  • Also, while looking at the map, you may notice its chambers sometimes blink. It also sometimes melts, revealing an eyeball which looks around in a creepy manner.

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