Drains health and power over time from the target and nearby encounter members, and converts it into health and power for the defiler's group. It costs power over time to maintain the spell and the defiler cannot move or cast spells, but the spell can be toggled off early if desired.
The amount of disease damage and the amount of encounter power decrease is dependent on the Intelligence of the Defiler.
I just got this spell and it does not Stifle or Root me. Also the statement above about Intelligence having anything to do with this spell must be outdated as we know Wisdom affects spell damage for Defilers.