Elemental Affinity (3.5e Feat)
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Elemental Affinity [Metamagic]
Allows user to change any spell using elements to another element of a chosen type.
Benefit: When you learn this feat, select one energy type (acid, cold, electricity, fire, or sonic). Any spell causing damage of one type may be changed to that of the chosen type instead. Spell effects other than elemental damage will not change. An elemental affinity spell uses a spell slot of the spell’s normal level, modified by any other metamagic feats.
Special: This feat may not be taken multiple times. A character taking this feat may not take Prismatic Energy Spell as a feat unless allowed by the DM.