master transmogrifist

Perhaps none of an arcane spellcaster's mighty powers is so versatile, useful, or spectacular as the ability to change into something else entirely. The master transmogrifist is a sorcerer or wizard who has chosen to specialize in spells that change his form. The polymorph spell and other shape changing transmutations offer the master transmogrifist t the ability to become a fearsome juggernaut of physical battle, a swift flying traveler, or the perfect spy. 

Favored Shape

your heritage lets you change into other creatures however its really hard to change to a similar creature for some reason. when you gain this feature you pick 3 creatures that are a CR of half of your sorcerer level or lower and you can turn into those creatures 1 time per long rest each using the true polymorph spell with no concentration. if you can cast any polymorph spell you may use your spell slots to turn into one of these creatures, doing it in this way however requires you to maintain concentration. the creature you choose can't be the same creature type as you (usually humanoid) but other than that you can choose any 3 creatures. when you level up you can change as many of these creatures as you want to match your current level. you also can cast the polymorph spell if you have the spell slots needed to cast it. 

extended change

all of your spells that transform you last twice as long. this does not affect spells cast on other creatures. a spell that transforms you is described as a spell that gives you a small change like alter self or a spell like polymorph that completely change your character.

manifest scenes

starting at 6th level, you can give your favored shapes a sense (dark vision, blind sight, etc) while in the form of another one of your favored shapes. starting at level 15 you can also manifest them while in your original form.

Shapechanger

starting at 14th level, you gain the shapechanger subtype and can cast alter self, if you already could cast it you learn a new sorcerer spell. when alter self is cast as a sorcerer it doesn't end unless you make it end or it is dispelled. you can also enter your favored shapes as a reaction to being hit.

manifest quality

when in one of your favored shapes you can give it 1 trait from another one of your favored shapes(multi attack is considered a trait). you can also give yourself a trait from 1 of your favored shapes every long rest.