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Kai was orphaned as a child due to humanity's prolonged war with the Covenant and became one of four hundred and ninety-seven such war orphans recruited for the first company of Spartan-IIIs. On December 27, 2532 Kai and the rest of the children were brought to the planet Onyx in the Zeta Doradus system. Multiple D77-TC Pelicans touched down on the parade ground at Camp Currahee at around 1953 hours to unload the recruits, who streamed out of the dropships at the behest of Senior Chief Petty Officer Franklin Mendez and were met by Lieutenant Kurt Ambrose. When the Mjolnir-clad Spartan-II first spoke, his voice carried by the camp's public address system, the children stopped moving and fell silent, amazed by the armored giant. As they crowded before him Kurt offered them the chance to become like him so that they might destroy the Covenant. He noted, however, that only three hundred slots were ultimately available and that the process of determining who would fill that roster would began that night. Mendez then ordered the children back onto the Pelicans and they each proceeded to shuffle aboard, after only some hesitation. After they were airborne once again each recruit was given a Falcon Wing aerial descent unit and told to jump from their dropship's rear bay if they wanted to be a Spartan. Following this, those who had jumped were recovered.
Alpha Company was trained from that point on by Lieutenant Ambrose and CPO Mendez at the Camp Curahee complex. The regimen mirrored that of the Spartan-IIs', with intensive physical conditioning and education conducted by hand-picked trainers and multiple on-site A.I.s. All training and indoctrination emphasized the significance of achieving objectives at any cost and a willingness to sacrifice for the UNSC. In 2536 Kai underwent the requisite Spartan augmentations, carried out aboard the UNSC Hopeful. Only around sixty percent of the four hundred and ninety-seven were considered to have been augmented successfully, but this did not automatically disqualify "failures" from being deployed regardless. Alpha Company graduated in 2536 and by October 16 of that year the three-hundred chosen to form its final incarnation had been selected and deployed.
He is assumed to be KIA along with the rest of Alpha Company during Operation: PROMETHEUS. However, this is under the assumption that he was not pulled out of Alpha Company prior to serve in a similar role as Carter-A259 and other Mjolnir-armored Spartan-IIIs.
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