Empower Spell (4e Feat)
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Empower Spell [Metamagic]
Re-roll damage dice of 1 (or 2) on one arcane attack power.
Prerequisite: 11th level, wizard
Benefit: Choose one arcane attack power that you know. Once per encounter, before you use the power, you can choose to make this an empowered spell. When you roll damage for an empowered spell, if any of the dice come up with a result of 1, you may re-roll them. You may repeat this until none of the damage dice show a 1. If the power uses d10 or d12 damage die, you may re-roll results of 1 or 2. You can't use this feat on a power that doesn't roll dice for damage. Each time you gain a level, you can choose to reassign the power to which this feat's effect applies.
Special: You can take this feat more than once. Each time you select this feat, choose a different power. You can't apply this feat to the same power more than once.