Curse of the ObaLevel 12 Uncommon

Lalali-Puy has taught you how to use the primal spirits to drain the vitality of an enemy

Sorcerer-King's Boon        13,000 gp

Power (Necrotic) ✦ Daily (Minor Action)

One enemy within 5 squares of you is blighted (save ends). While blighted and within 10 squares of you, that enemy takes necrotic damage the first time on each of your turns that you deal damage to a creature other than that enemy. The damage equals 2 + your Wisdom modifier.

Published in Dragon Magazine 395.