Elementalist (3.5e Trait)
From D&D Wiki
You are a master of elemental magic, but falter when casting certain types of other spells.
Benefit: +1 caster level when casting a spell that makes use of the acid, cold, electricity, fire, or sonic descriptors.
Drawback: -2 caster level when casting any other type of damaging spell.
Roleplaying Ideas: You would rather hurl a fireball or lightning bolt than a magic missile or enervation spell any day of the week.