Third Sphere of Expansion
The Third Sphere of Expansion, launched in 997.M41, was the third campaign of expansion of the Tau Empire. Launched in the aftermath of the Great War of Confederation, the campaign was overseen by Commander Shadowsun.
With the Orks defeated in the Great War of Confederation, Ethereal Supreme Aun'va knew the time was ripe for a new phase of expansion. The great war against the Orks had pushed Tau civilization to a setting of total war, and they now could support campaigns larger then any before. The large and newly experienced caste of Fire Warriors would be bolstered with improved ship engines and stasis chambers, allowing for expeditions to be launched over much greater distances. Thus unlike past spheres of expansion which focused on specific star clusters, the Third Sphere encompassed a much larger region of space.
The expedition under Commander Shadowsun first crossed the Damocles Gulf and moved into Imperial space. Thanks to Water Caste agents, Gue'vesa humans were mobilized to conduct reconnaissance against Imperial forces. Some Imperial worlds simply surrendered at the first sight of the Tau, welcoming the Water Caste ambassadors and pledging for their cooperation. However most humans rejected Tau overtures due to their distrust of all xenos and Shadowsun and her armies were forced to sweep down in a series of precision strikes. The sparsely deployed imperial defenders proved unable to stem the Tau advance. Soon the northernmost sector of the Damocles Gulf was in Tau hands while the Galactic West was cleared of Hrud, Orks, and rebel humans. New Septs established during the Third Sphere of Expansion include Ksi'm'yen, Mu'gulath Bay, and Fi'rios.
Bowed by her initial success, Shadowsun rapidly led deeper advances. However the deeper she advanced, the greater the resistance she encountered. Seeking to avoid over-extension and the depletion of her forces, she instead broke up her forces into fleets, scattering them to a dozen different headings. Each began a devastating series of hit-and-run attacks which the Imperium proved unable to effectively counter. A pivotal battle was fought on the Hive World of Agrellan, where Shadowsun's Warriors were accompanied by Aun'va himself, who sought to inspire the Empire's troops. During the battle, the newly deployed XV104 Riptide Battlesuit was unleashed and laid waste to hordes of Imperial Guard heavy tanks and static defensive lines. Agrellan was renamed Mu'gulath Bay and soon the entire system fell with it. Shortly after the victory at Mu'gulath bay however Shadowsun became overconfident and suffered a stinging defeat at Voltoris.
Soon enough the Imperium would counterattack with elite Space Marine forces at the Zeist Sector, but this too was part of Shadowsun's plan. As a diversion, this system was sacrificed for the Greater Good and forces there was instructed to stall the Space Marines for as long as possible. Meanwhile, Shadowsun struck deeper into more desirable neighboring systems. The worlds of the Imperium toppled one after another in the face of this precision assault. The Empire suffered a major setback when Mu'gulath Bay was destroyed during an Imperial attempt at reconquest.
Due to a multitude of vicious Imperial counterattacks in the Damocles Gulf region, the Third Sphere eventually ground to a halt after its path was blocked in the Second Battle of Mu'Gulath Bay. It was followed by the ill-fated Fourth Sphere and Fifth Sphere.
- 1: Codex: Tau Empire (6th Edition), pgs. 31–33
- 2: War Zone Damocles: Kauyon, pgs. 6–7
- 3: War Zone Damocles: Mont'ka, pgs. 105–110
- 4: Warhammer 40,000 8th Edition Rulebook pg. 134
- 5: Codex: Tau Empire (8th Edition) pg. 22