Shas'O Kais was a student of Commander Puretide. Under Puretide's tutelage, Kais became a master of the Monat ("Lone Warrior") method of combat.
In 740.M41, Shas'O Kais was dispatched to quell the troubles on Kronus, and brought along the Fire Caste and the Tau allies, the Vespid and Kroot. He was also dispatched with the Ethereal Aun'el Shi'Ores to secure and hold the capital city on Kronus. The planet was caught in a battle between the Imperium of Mankind's Imperial Guard and Blood Ravens Chapter of Astartes, the Eldar, and the Necrons. A strong yet merciful commander, O'Kais often offered his enemies multiple chances to surrender, with refusal to serve the greater good resulting in the enemy's total annihilation. However, the Blood Ravens managed to drive the Tau forces off the world during the campaign.
After the end of the Damocles Gulf Crusade, Shas'O Kais was put into stasis to be preserved until he was needed, and later revived, though the exact time of his revival was not recorded.
In 243.M42, he was deployed to a mission on Duskenwald. Using a XV95 Ghostkeel to attack a Dark Angels facility housing several psykers. Killed his intended targets, and several Astartes, his battlesuit was disabled by an orbital bombardment, forcing him to flee. The data from this battle was recovered by the Tau to be used as the basis for training a force of Tau with skills similar to his.
Kais wears experimental XV22 Stealth Battlesuit armour, a symilar type as Commander Shadowsun, which throughout the campaign gains a Jetpack, Advanced Sensor Array and Stealth field generator. Initially armed with only a Burst Cannon, Kais has access to a plethora of ranged weapon upgrades including Missile Pods, a Fusion Blaster and a Plasma Rifle. He can also be accompanied by various Shield drones and Gun drones.
'Kais' means 'Skilful' in T'au language.
The name 'Shas'la T'au Kais' was also featured in the first person shooter for the PC and Playstation 2, which was later adapted into a novel: Warhammer 40,000: Fire Warrior, the protagonist being a Tau warrior first fighting the Imperium, then the forces of Chaos. However, this Kais is unrelated to Shash'O Kais, as O'Kais was a student of Commander Puretide, who died before the Damocles Gulf Crusade, while La'Kais wouldn't even finish his basic training until 200 years after the Damocles Gulf Crusade
- 1: Warhammer 40,000: Dawn of War - Dark Crusade
- 2: Warhammer 40,000: Fire Warrior (Novel)
- 3: Codex: Tau Empire (6th Edition), page 29
- 4: Codex: Tau Empire (8th Edition)
- 5: War of Secrets (Novel) by Phil Kelly, Tau Xenolexicon
- 6: Dawn of War II