Prerequisite(s): Knowledge (arcana) 10 ranks, Spellcraft 10 ranks, caster level 10th, any three metamagic feats

Benefit: Choose one metamagic feat that you already know. The level cost of that metamagic feat is reduced by one (to a minimum of +1). For example, using Metamagic Mastery on the Maximize Spell feat would allow you to cast a maximized fireball as a 5th level spell, instead of the normal 6th level spell slot it would take (+2 spell levels instead of +3 spell levels).

Special: This feat may not applied to metamagic feats that have a variable level cost, such as Heighten Spell.