Knowledge (any one).
identify (3rd), invisibility (5th), dispel magic (7th), dimension door (9th), overland flight (11th), true seeing (13th), greater teleport (15th), power word stun (17th), wish (19th).
Combat Casting, Improved Counterspell, Improved Initiative, Iron Will, Scribe Scroll, Skill Focus (Knowledge [arcana]), Spell Focus, Still Spell.
Whenever you apply a metamagic feat to a spell that increases the slot used by at least one level, increase the spell's DC by +1. This bonus does not stack with itself and does not apply to spells modified by the Heighten Spell feat.
Magic comes naturally to you, but as you gain levels you must take care to prevent the power from overwhelming you.
Arcane Bond (Su)
At 1st level, you gain an arcane bond, as a wizard equal to your sorcerer level. Your sorcerer levels stack with any wizard levels you possess when determining the powers of your familiar or bonded object. Once per day, your bonded item allows you to cast any one of your spells known (unlike a wizard's bonded item, which allows him to cast any one spell in his spellbook). Once per day, your bonded item allows you to cast any one of your spells known (unlike a wizard's bonded item, which allows him to cast any one spell in his spellbook). This ability does not allow you to have both a familiar and a bonded item.
Metamagic Adept (Ex)
At 3rd level, you can apply any one metamagic feat you know to a spell you are about to cast without increasing the casting time. You must still expend a higher-level spell slot to cast this spell. You can use this ability once per day at 3rd level and one additional time per day for every four sorcerer levels you possess beyond 3rd, up to five times per day at 19th level. At 20th level, this ability is replaced by arcane apotheosis.
New Arcana (Ex)
At 9th level, you can add any one spell from the sorcerer/wizard spell list to your list of spells known. This spell must be of a level that you are capable of casting. You can also add one additional spell at 13th level and 17th level.
School Power (Ex)
At 15th level, pick one school of magic. The DC for any spells you cast from that school increases by +2. This bonus stacks with the bonus granted by Spell Focus.
Arcane Apotheosis (Ex)
At 20th level, your body surges with arcane power. You can add any metamagic feats that you know to your spells without increasing their casting time, although you must still expend higher-level spell slots. Whenever you use magic items that require charges, you can instead expend spell slots to power the item. For every three levels of spell slots that you expend, you consume one less charge when using a magic item that expends charges.