Harbinger Eidolon Faction Guide: Corruption, Shrouds, and Null Weapons
Verified Eidolon mechanics: planetary and unit corruption, shrouded worlds, null weapons, cloaking, psionics, and phase echoes.
Quick Answer
The Eidolon spread corruption and turn it into offensive tempo. Fully corrupted worlds can be shrouded; corrupted units gain offense while losing hull; null weapons negate shields and spread corruption.