Jellicent is a large jellyfish-like Pokémon whose appearance varies based on gender. Both genders have five tentacles, two of which are long with petal-shaped ends. The remaining three are short and tapered. A male is blue with a short, white crown, and a white, mustache-like collar. Its eyes are red with blue sclerae, and there is one eyelash over each eye. Its long tentacles have white edges, while its short tentacles have white spots. A female is pink with a tall, white crown and a puffy, white collar. Its eyes are blue with red sclerae and surrounded by two eyelashes. Its mouth is red and heart-shaped. The long tentacles have white edges like the male, but the short ones have white frills.
Jellicent can absorb seawater and project it from its head, which lets it move forward in the sea. Jellicent's body composition is similar to seawater. Schools of Jellicent are known to gather for prey during a full moon. Any fancy cruise ships, tankers, or crew that wander into the oceans where it dwells are never found again, and it is rumored that it drags these ships or tankers into the sea and preys on its passengers. It can create lairs from sunken ships. It is known to feed on life energy, where the more it drains, the bigger its crown gets. Jellicent are highly feared by fishers.
Although female Dream World artwork exists, any Frillish or Jellicent uploaded to the Global Link will use the male artwork, regardless of their gender.
Jellicent and its pre-evolution were designed by Mana Ibe.
Jellicent and its pre-evolved form were most likely inspired by the Nurarihyon, a jellyfishyōkai that is either shown as a demonized jellyfish or as a jellyfish-like man who wears refined, sometimes regal, clothing. It is also possible that they were inspired by the Kurage no Hinotama, a sort of jellyfish-like will-o'-the-wisp. Its design is inspired by the jellyfish (in particular the crown jellyfish and jelly blubber) and monarch attire; the male's appearance is based on a king's while the female's is based on a queen's.
The moon jellyfish may have influenced Jellicent being a Ghost type. Its dangerous ability to prey on humans, in self-defense of its habitat, is possibly based on the box jellyfish and other highly venomous species of jellyfish that can kill humans. Jellicent and its pre-evolved from may also be inspired by the Stygiomedusa, also known as the Phantom Jelly, a very rarely seen deep sea jellyfish with fabric-like arms. The two larger tentacles Jellicent possesses are more similar to those of squids than the tentacles of real jellyfish. Jellicent also has traits in common with sea monsters like the Kraken, most notably its rumored penchant for destroying ships and feeding on the crew.
Jellicent may be a combination of jellyfish and magnificent or translucent.
Burungel may be a combination of ブルンブルン burunburun and ゲル gel