Yrrej was a magma cube in CaptainSparkelz Survival Series. He was found in the Nether (where magma cubes naturally spawn). He was extremely small, so Jardoon thought the magma cube couldn't hurt him. However, Jardoon was incorrect; magma cubes can attack players, no matter how big or small they are. After discoving this, he deemed this magma cube Jerry's opposite. Therefore, his name became Yrrej (Jerry spelled backwards). It is unknown if Yrrej is still in the Nether or not.
- Captain might have got the idea of calling him Jerry backwards from Dragon Ball Z because of the character Uub being Buu backwards.