Phoenix Logs/Flood Units/Blisters

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Phoenix log artwork

Incubation chambers.

Non-sentient animals or corpses not harnessed for combat forms are seeded with Flood cells and transformed into infection form-filled sacs. These diseased growths are one of the most pernicious aspects of the Flood, and a single spore could potentially transform an entire planet's biosphere into quivering masses of diseased mucus and bile if left unchecked.

Blisters "hatch" infection forms when disturbed. Destroying them at a distance is almost always the best option.