Dungeons & Dragons 3.5 Feat: Alternative Source Spell

You can prepare any of your spells as either divine or arcane.

Ability to cast both divine and arcane spells.

 

You can choose to prepare any of your divine spells as arcane spells or any of your arcane spells as divine spells. An alternative-sourced spell uses up a spell slot from the class that normally grants the spell. Such a spell is prepared normally. An alternative-sourced spell is cast as if your caster level were 1 level lower. For example, a 1st-level cleric/6th-level wizard casts a divine fireball as a 5th-level wizard.