Spellsplit (3.5e Feat)
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Allows the caster to split his high-level spells into multiple low-level ones.
Arcane efficiency, Any Spell Focus, ability to cast 5th level arcane spells, must have three 5th level or higher spell with the same school choosen for spell focus.
The caster may remove a spell from his spell slot as if it had been cast and gain two temporary spell slots of 3 levels lower. This can be used as a full round action, and one split spell may be cast during the turn.
For Example, Mumford the Mage is in a duel with a druid, and has no more spells except a disintigrate. Knowing that a fireball would be harder to save against with druid saves, and wishing to also defeat the animals the druid has summoned, Mumford uses a full round action to split his disintigrate into two fireballs. With one full round action, he casts the fireball and gains an extra prepared fireball, in case the druid and his minions survive the turn. Mumford can then split his fireball spell into 2 magic missle spells, and so on and so forth.
This is a feat that may be acquired as a lower-spell bonus feat.