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Preserve Scroll (3.5e Feat)
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Preserve Scroll [Psychic]
When casting a spell from a scroll, you have a chance of preserving the scroll for re-use. You accomplish this by powering the spell with your own magic rather than that of the scroll, which involves expending a spell of at least equivalent level, and of the same type (thus, you can't preserve a divine scroll by expending an arcane spell). You must meet all the usual requirements for using the scroll, plus the additional requirement of having a spell of high enough level to power it (hence, you can't use this power when casting a spell which exceeds your own casting ability). You must also have any components required for the spell you'll be casting (the one on the scroll). Caster level for the spell will be your own or that of the scroll, whichever is lower. This ability allows wizards, clerics etc to use their own spell energy to cast spells they haven't learned or prepared: Sorcerers, Bards etc may use their own spell energy to cast spells they haven't learned. Success is determined by a Spellcraft check with a DC of 10 plus twice the spell's level. Failure indicates that the scroll's power is consumed, rather than your spell: the spell still works, and you keep your own spell (and any material component or experience points normally required), but you lose the spell on the scroll (you can attempt a Spell Recovery check at a -10 penalty to safely abandon the casting and keep the scroll intact: fail this, however, and you abandon the casting AND lose the spell from the scroll).
Normally, you must cast the spell with whatever metamagic enhancements were incorporated into the scroll (and modify the level of the powering spell accordingly). If you also have the Impromptu Metamagic power, you can attempt to add or subtract metamagic enhancements, but this is risky: failure of the Impromptu Metamagic check causes the Preserve Scroll check to automatically fail.