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The player and partner speak to Whiscash
Whiscash (Japanese: ナマズン Namazun) is a non-player character in Pokémon Mystery Dungeon: Red Rescue Team, Blue Rescue Team and their remake, Rescue Team DX. It is implied that Whiscash makes an appearance in Pokémon Super Mystery Dungeon as well.
In the games
Whiscash resides in Whiscash Pond and is first met there. He enjoys telling stories and is the first to tell the player and partner of the Ninetales legend. Whiscash is seen in Whiscash Pond throughout the whole game. He is the wisest Pokémon in Pokémon Square, and the second wisest in the Pokémon world, second only to Xatu.
After the end credits, he gives the player the HM Dive, which enables entrance to Stormy Sea. He also unlocks Solar Cave, where HMs Waterfall and Surf can be found. A replacement Dive can also be found there.
In Pokémon Super Mystery Dungeon, a Whiscash that is likely to be the same is connected with Emolga, Charizard, Seviper, Tyranitar, and Alakazam. The Charizard, Tyranitar, and Alakazam are likely Team A.C.T. He can be encountered at Baram Town on the Air Continent.
Pokémon Super Mystery Dungeon
In the anime
Whiscash appeared in Pokémon Mystery Dungeon: Team Go-Getters Out of the Gate!. Like in the games, he resides at Whiscash Pond. Whiscash was first seen trying to comfort a Pichu whose older brother Pikachu had gone missing in Sinister Cave. He told Pichu that Team A.C.T. would save Pikachu, but Snubbull told him Team A.C.T. was already on a mission. Just when it seemed there were no other Teams available to rescue Pikachu, the newly formed Team Go-Getters and Team Meanies showed up. Whiscash agreed that both Teams should go and rescue Pikachu.
For more information on this Pokémon's species, see Whiscash.