Jellien Patrick greatly resembles the real Patrick Star except he has dark, reflective, round eyes. This is a common trait in the rest of the Jellien clones too.
Jellien Patrick is created after the Evil Alien Jellyfish Overlord creates a Jellien after having eaten a jellyfish. The Jellien then eats a sleeping Patrick and carries him away. Jellien Patrick then meets up with SpongeBob, who spots that Patrick caught a Jellien, leading SpongeBob to think it is an ordinary jellyfish. Jellien Patrick then catches a whole smack of Jelliens. He then tricks SpongeBob to give them away to each of his friends. After turning Squidward into a Jellien, Jellien Patrick takes over SpongeBob's position as fry cook at the Krusty Krab, where he helps serve Krabby Patties, without the mayonnaise.
He is then finally destroyed after SpongeBob sprays him with mayonnaise when Jellien Patrick and Sandy are about to take on the Evil Alien Jellyfish Overlord.
Jellien Patrick behaves very differently from Patrick. His only course of action is to plant Jelliens on the heads of citizens and turn them into Jellien clones. Like all Jelliens, Jellien Patrick vehemently despises mayonnaise as when SpongeBob tells him that he is going to get more in the back, Jellien Patrick quickly turns his head around and loudly shouts out "No mayonnaise!"
Jellien Patrick is the only Jellien Clone that has met SpongeBob but does not try to harm him by any means. All other Jelliens try to get SpongeBob to wear Jellien hats; some would also hiss or growl at the non-Jellien SpongeBob.
Jellien Patrick was apparently the last of the Jelliens to be destroyed by mayonnaise.