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
For more information on this Pokémon's species, see Whiscash.