Pururill

Pururill is a jellyfish-like Pokémon resembling young royalty. Regardless of gender, it has a round head with a crown-like tuft, and five tentacle-like appendages: two serving as arms and three as the lower half of its body. It has oval eyes with white pupils, and a collar around its neck. It has invisible poison spikes on its appendages. As a male Pururill, it is blue, with smooth appendages and a triangular crown. It has red eyes with blue sclerae and a straight eyelash on each eye, its collar is wavy, and it appears to be frowning, but in the anime it is shown to smile rarely. As a female Pururill, it is pink, with wavy appendages and a round crown.

It has blue eyes with red sclerae and a curled eyelash on each eye, its collar is frilled, and it appears to be smiling. Female Pururill have slightly longer stingers, while male Pururill have bigger collars.

Pururill is a hadopelagic Pokémon which lives in dens about 5 miles (8 kilometers) under the sea surface. Because of this, it can cope with extremely dark and highly pressurized sea conditions. It is carnivorous; it gently floats around in waves until it can strike its prey. It makes its victim numb with the use of its poison spikes and takes it to its deep den. Its arms are filled with tens of thousands of poisonous stingers. There is a legend where Pururill are said to have been created from transformed residents of a sunken ancient city.

(Source: Bulbapedia)