Pluton

Pluton is a genetically modified Jiralhanae designed to counter the strength of the Spartans. Pluton is a non-canon character presented in the anime short Odd One Out in Halo Legends.

Biography
Pluton was created to counter the strength of the Spartans. Pluton is sent to the planet Cronky to kill the Master Chief but ends up fighting SPARTAN-1337 instead. After some chaos Mama opens a slipspace portal and fires a life boat at Pluton sending him through the slipspace portal. Pluton is then seen with his head trapped in the bottom of a Halo ring.