Mr. Briney's Whisko usually follows the old man's ship. As Ruby was rescued by Mr. Briney and Peeko, Whisko felt a certain movement, as Mr. Briney explained earthquakes could occur throughout the sea. Ruby remarked none of Mr. Briney's Pokémon looked beautiful. Though annoyed by that, Briney showed certain Pokémon of Hoenn that Ruby thought how beautiful they looked.
While seeing Wallace's performance, Ruby remembered Mr. Briney had a Whiscash. However, seeing Wallace's Whiscash, Philip, Ruby noted how much refined it looked.
None of Whisko's moves are known.