Codex: T'au Empire (2018), p39 — M41 Fourth and Fifth Sphere Expansions

Plague Wars

Commander O'Kais is sent to prepare the verdant world of Kellik for colonisation. Unfortunately, Plague Marines of the Death Guard have already made landfall, and are in the process of pouring the disease-ridden, liquefied remains of their sacrificial victims into Kellik's great lakes. T'au gunships and Piranhas knife into the Heretic Astartes, overwhelming dozens of Plague Marines with bursts of incinerating plasma fire. However, the Death Guard had already seeded their foul corruption deep into the bedrock of Kellik. Foetid creatures begin to crawl from the tainted waterways in their thousands, and clouds of fat-bodied flies block visor displays and clog helmet rebreathers. The Plague Marines rally and regroup, chortling wetly as they unleash brutal fusillades of bolter fire that burst open T'au bodies like ripe fruit. Commander O'Kais refuses to abandon his mission even in the face of this repulsive contagion, and the surface of Kellik becomes host to a deluge of blood and bile.

[...]

Battle of the Startide Nexus

Mere months after the Fourth Sphere survivors rejoined their people, an enormous Death Guard armada tears its way from the warp and emerges in the heart of the Nem'yar Atoll, before the mouth of the Startide Nexus itself. The Chaos fleet launches attack ships and boarding claws filled with Heretic Astartes at the star fortresses guarding the spatial rift. The shocked T'au defence fleets react with remarkable speed, blasting many of these vessels to atoms, but many more slip through the barrage and spill packs of frenzied killers into tide-locked arcologies and stellar fortifications. A furious battle rages. The T'au know that if the Nexus falls, a route to the heart of the empire will be left open. The warriors of the Fire caste fight with desperate courage, selling their lives by the thousand to repel the invaders. Commander Shadowsun leads an immense counter-attack into the heart of the Chaos fleet, blasting daemonic enemies and hulking Plague Marines into a putrid mist with each cannonade from her twin fusion blasters. Yet even her desperate heroics surely cannot hold back Nurgle's chosen Legion for long...