Role in the series
The Jellyfish first appeared in the episode in the special '"The Great Never Sea Conquest". When the evil Mer-wizard, Lord Fathom is released from an underwater prison, he sets out to take over the Never Sea by awakening the legendary giant, three-headed serpent, the Strake. The The Jellyfish where among the various sea creature being control by Lord Fathom during his hostile take over of the Never Sea.During the final phase of the battle between Jake and Lord Fathom,King Neptune appears and tells Jake that all he needs to defeat Fathom and the Strake is to believe in himself. Using the powers of his sword, Jake finally defeats Fathom and the Strake. He then re-imprisons the Strake and destroys the Darklight Emerald, freeing Queen Coralie, Marina, Stormy, and the sea creatures.The Jellyfish are last seen among the various sea creatures chasing Lord Fathom and Sinker away.