Enervate Spell (4e Feat)
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Enervate Spell [Metamagic]
Add necrotic damage type to arcane spell and weaken targets
Prerequisite: Wis 13, wizard, 11th level
Benefit: Before using an arcane attack power, you can choose to take a -2 penalty to each die of damage rolled with the power. If you do so the power gains the necrotic keyword and deals necrotic damage in addition to its normal damage type. If the power is encounter or daily, targets hit are weakened until the end of your next turn. If the power is at-will, targets take a -2 penalty to damage rolls until the end of your next turn. The penalty increases to -4 at 11th level and -6 at 21st level.