Instant Spell (3.5e Feat)
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Instant Feat [Metamagic, Epic]
You can cast spells instinctively.
Prerequisite: Quicken Spell, Caster Level 30, able to cast 12th-level spells.
Benefit: Casting an instant spell is a free action that may be taken even when it isn't your turn, but you must not be affected by any effect that would prevent you from casting spells or reacting to danger. You can perform another action, even casting another spell, in the same round as you cast an instant spell. A spell whose casting time is more than 1 full round action cannot be quickened. An instant spell uses up a spell slot twelve levels higher than the spell’s actual level. Casting a quickened spell doesn’t provoke an attack of opportunity.
Special: Conditions that may prevent the use of an instant spell include, but are not limited to: paralysis, flat-footedness and death.