Qwilfish

Qwilfish is a Water, Poison-type Pokémon from the Johto region. The Normal form does not evolve into or from any other Pokémon. It has a Hisuian form that is Dark, Poison-type and evolves into Overqwil when fed candies.

Possible attacks
Normal form=

Attack availability
Hisuian form=
 * Acid Spray:  added  on March, 2019
 * Fell Stinger:  added  on December, 2019