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Sinister Cave (Japanese: あやしい どうくつ Dubious Cave) is a dungeon in the Mystery Dungeon world that was featured in the special episode of the anime Pokémon Mystery Dungeon: Team Go-Getters Out of the Gate!. Despite the fact that the special is based on the games Pokémon Mystery Dungeon: Red Rescue Team and Blue Rescue Team, Sinister Cave did not appear in either of these games. Instead, it is based on two dungeons encountered early in these games: Mt. Steel and Sinister Woods.
Team Go-Getters, a newly formed Rescue Team, heard from the Whiscash at Whiscash Pond that the older brother of a Pichu, a Pikachu, was stuck at Sinister Cave. It was decided that a Rescue Team had to save Pikachu, but since Team A.C.T. was already occupied with another mission, another Rescue Team had to go. Team Go-Getters, as well as Team Meanies proposed to go to Sinister Cave to rescue Pikachu.
Team Go-Getters arrived at the cave and walked through it for some time without any trouble, lighting up the darkness with the fire on the tail of the Team's Charmander. They heard the noise of someone in need of help from behind a rock and Charmander destroyed the rock with its Metal Claw. It was revealed that the noise came from the Pichu who had asked them to search for his older brother earlier. Pichu was so tired that it fainted, but Team Go-Getters helped it get up with an Oran Berry. Pichu told the Team that Team Meanies had come to the cave before them and that he had met them. They had then locked Pichu up by placing a boulder in the way. Pichu now decided to go along with Team Go-Getters.
Somewhat later, they came across a large group of sleeping Shroomish. The Squirtle of the Team accidentally woke one up, which in turn woke its fellow Shroomish and made them all go angry. The Team had to run from them, but Charmander eventually scared them off with his newly learned Flamethrower. The Team soon reached the end of the cave and arrived at a mountainous landscape were they encountered a Skarmory. They fought the Skarmory and defeated it and rescued Pichu's older brother Pikachu.
Pokémon seen in Sinister Cave