Optional Rule: Energy Conversion

Some players want to allow their character a specific theme, but finding spells to fit that theme isn't always easy. Consider allowing characters in your game to find or know alternative versions of existing spells.

Under this optional rule, any time a character is granted a new spell or power known, or adds a spell to their spellbook as a result of gaining a new level, or when a character prepares spells directly from their class list (such as a Cleric), they may choose to learn or prepare a version of that spell which has an altered damage type.

For example, a character may choose to learn acidic burst instead of fireball. The spell behaves exactly as fireball, except that it deals acid damage instead of fire damage, and corrodes weak objects instead of setting them on fire.

Once a spell is added to the character's list of spells known or the character's spellbook, it cannot be altered; a new version of the spell must be learned to gain an alternative element.