From Halopedia, the Halo wiki
SPARTAN-1337 trained with his fellow Spartans, which John-117 considered the best. During his Spartan career, 1337 has apparently fell out of a Pelican in multiple instances.
During one particular mission on the planet Cronkee, the fourth planet in the Unicorn system, 1337 slipped and fell out of a Pelican. As he tried to hail the Pelican, he discovered three children standing behind him. While 1337 was attempting to make contact with John-117, still annoyed at the children who were following him, Pluton suddenly appeared. 1337 told the kids to escape and engaged Pluton in a battle. He got knocked out by Pluton, but he was helped by Guy and May, older siblings of the three children. May and Guy told 1337 about "Mama", who fought off bird headed pirates once and that they could help. 1337 hesitated but eventually agreed as the three fought Pluton. When Pluton began charging up again, SPARTAN-1337 distracted the Jiralhanae by shouting, "Hey, what the heck is that?!" to make their escape. Suddenly, the crashed ship that SPARTAN-1337 found earlier creates a Slipspace rupture. The ship fired a MAC at Pluton, causing him to be thrown into the rupture. May, Guy, Loo, Sap, and Pom returned home, while 1337 was contacted by Master Chief. Master Chief ordered 1337 to head to the rendezvous point, but 1337 told Master Chief that he might be a little late as a pterodactyl suddenly appeared and carried him off into the horizon.
Personality and traits
Despite being accident-prone and clumsy, SPARTAN-1337 is quite cocky and confident in his abilities despite his comical blundering. 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