Battle of the Startide Nexus
|Conflict||Fifth Sphere of Expansion|
|Outcome||Apparent Tau victory, Death Guard status unclear|
|Significant|| Death Guard|
Daemons of Nurgle
The battle began mere months after the commencement of the Fifth Sphere of Expansion when a sizable Death Guard armada invaded the Tau Empire's newly colonised area of space, known as the Nem'yar Atoll. The Chaos Space Marines launched boarding craft attacks on the Orbital Stations guarding the entrance to the Startide Nexus, which is located within the Atoll and serves as a stable dimensional pathway between the Atoll and the Tau Empire proper. The shocked Tau responded with remarkable speed, destroying many vessels but were overwhelmed by the sheer numbers. The Death Guard were able to board the stations, and a vicious melee battle erupted. Many thousands of Tau lost their lives in the desperate defense of the Nexus.
When Commander Shadowsun learned of the assault she immediately responded, and upon arrival broke down her fleet into small battle groups, each with dedicated targets and responsibilities. Some relieved the defense stations while others engaged Death Guard fleets. Others engaged in baiting attacks and feigned retreats before striking again. Despite these tactics however the Death Guard advance could still not be halted. Death Guard vessels advanced on the Nexus and Shadowsun considered that victory might not be possible. She became determined to warn the Tau Empire of the coming threat and sent a drone into the Nexus. Though Death Guard vessels managed to enter the Nexus, others suddenly withdrew. Even more perplexing was that the Death Guard never emerged on the other side to the waiting Tau defense fleets. For months the Tau stood at high readiness, waiting for a foe that never appeared. The Tau are busy analyzing what exactly the Death Guard objective in the battle was. 
The Battle proved costly to the Tau Fifth Sphere of Expansion, whose fleet was mauled by the campaign. This has blunted the momentum of the Fifth Sphere, and thus a Sixth Sphere of Expansion is being planned.
- 1: Codex: T'au Empire (8th Edition), pg. 39 - March of Conquest: Battle of the Startide Nexus
- 2: Psychic Awakening: The Greater Good, pgs. 4-5
- 3: Codex: T'au Empire (9th Edition), pgs. 26-27