Metamagic Mastery (Sorcerer Revised)

Additional (20th) level feature

You have gained immense control over the magic which fuel your spells. When you use metamagic to augment a spell, you may use one additional metamagic option you know, which the spell meets the criteria for, expending sorcery points for each metamagic individually. This feature can only be used once for a spell.

You can use this feature a number of times per day equal to your Charisma modifier (minimum 1).