Advanced Shapechanging

Increase your Intelligence, Wisdom, or Charisma score by 1, to a maximum of 20. Additionally, when you use your Shapechanger ability to mimic another creature, you gain the ability to speak, read, and write one language of your choice that the creature knows. You retain this knowledge as long as you maintain the creature's form. When you change to another form or revert to your true self, you immediately lose the ability to speak the associated language.