From Halopedia, the Halo wiki
SPARTAN-1337 is a SPARTAN-II Commando of the UNSC Naval Special Warfare Command. He is the main character of Odd One Out, the non-canon and satirical interpretation of the Halo universe produced by Toei Animation for Halo Legends.
He is depicted as being extremely accident-prone and clumsy. All throughout Odd One Out, Spartan 1337 is quite cocky and confident in his abilities despite his comical blundering. Also, none of the inhabitants of planet Cronkee are aware of his status as a SPARTAN-II: he introduces himself with great gusto which does nothing to clarify his rank or status as one of the self-proclaimed "strongest warriors in space".
List of appearances