Incantatrixes are the definitive practitioners of metamagic in Faerûn, devoting themselves to the study of spells and techniques that affect other spells. They deal with magic in its raw form, shaping it according to their own desires rather than any external laws of magic. They can apply their deep understanding of metamagic to alter spells their allies cast, and even spells that have already been cast. Incantatrixes are also adept at countering and negating the magics of other spellcasting creatures and dealing with creatures who exist simultaneously on more than one plane. The majority of incantatrixes are female, while males were rare and known as incantatars. The term metamage is sometimes used as a gender-neutral reference to both incantatrixes and incantatars, but the term is not strictly accurate.

Incantatrixes tend to act independently, but because they often have similar aims and interest, they sometimes join together in loose coalitions to combat common foes—notably those individuals who use magic in a dangerous, irresponsible manner. An incanatrix seeks to police the unrestrained use of magic about her home, much like a druid protecting her forest. Likewise, since they dislike extraplanar intrusions onto the Material Plane, most incantatrixes see the destruction of active portals to other planes as their responsibility. Thus, an incantatrix is usually a knowledgeable source if information on functional portals in the area. 
(See Dragon Magazine #90, Cult of the Dragon, Magic of Faerûn, and Player’s Guide to Faerûn for the original versions of the incantatrix.)  

Incantation

Your extensive practice and study of raw magic allows you to learn spells from the wizard class. When your Spellcasting feature lets you learn or replace a sorcerer cantrip or a sorcerer spell of 1st level or higher, you can choose the new spell from the wizard spell list or the sorcerer spell list. You must otherwise obey all the restrictions for selecting the spell, and it becomes a sorcerer spell for you. To pursue the incantatrix path though, you cannot chose any necromancy spell in your list of known spells.

In addition, you learn the following spells when you reach specific class levels. Those spells does not count against the number of spells known for your class.

1st level: Detect Evil and Good
9th level: Dispel Evil and Good
11th level: Forbiddance 

Spellsense

You have an innate understanding of magic. At 1st level you gain proficiency in the Arcana skill. You also automatically know the spell school and level of every spell being cast by a creature that you can see or hear while casting. 

In addition, every time you are affected by a divination spell that grants you any kind of sight-based benefit (such as see invisibility or darkvision), you are also able to see through the Ethereal Plane and influence creatures on that plane with your spells as if they were on your own plane.

Improved Metamagic

At 6th level you gain another Metamagic option from your class list. In addition you can use your reaction to apply one of your Metamagic options to a spell being cast by a willing ally spellcaster. You spend sorcery points as if you were using it normally.

Concentration Mastery

Starting at 6th level, you have advantage on concentration checks and when you broke your concentration on a spell, whether willingly or because of a failed concentration check, you can use your reaction to have that spell last until the end of your next turn. 

Magic Drain

Starting at 14th level, as an action you can drain power from magic items you hold to restore your sorcery points.  If the item drained has charges you restore 1 sorcery point per 2 charges drained, up to your Charisma modifier. If the item does not have charges you temporarily drain all its magic powers for 8 hours, and you gain 1 sorcery point from a common magic item, 2 from an uncommon item, 4 from a rare item, 7 from a very rare item, and 10 from a legendary item. You cannot drain magic from consumable items, sentient magic items or artifacts. Once you use this ability, you cannot drain power from magic items until you complete a long rest.

Seize Spell

At 14th level, as an action you can spend 3 sorcery points to cast dispel magic as a 3rd level spell. You can increase the spell level by 1 per each extra sorcery points you decide to spend, up to the maximum level of spells you are able to cast. When you successfully dispel a spell in this way, you can instead seize control of it (and start concentrating if it's required) and immediately decide to change the targets and the area of effect of the spell, as if you were casting it in that moment. The duration of a spell seized this way does not changes.

Spell Absorption

At 18th level, as a reaction you can spend 3 sorcery points and cast counterspell as a 3rd level spell. You can increase the spell level by 1 per each extra sorcery points you decide to spend, up to the maximum level of spells you are able to cast. When you successfully counter a spell in this way, for the next 8 hours you know the spell and can cast it once without using your spell slots. In addition the original caster can’t cast that spell until the 8 hours have passed.