Shapechanger (Bat Form)

Vampires are known for their ability to shift from form to form. You gain the shapechanger tag and if you are not in sunlight or running water, you can use your action to polymorph into a Tiny bat or a Medium cloud of mist for 1 minute, or back into your true form.

Bat Form: While in bat form you can't speak, your walking speed is 5 feet, and you have a flying speed of 30 feet. Your statistics, other than your size and speed, are unchanged. Anything you are wearing transforms with you, but nothing you are carrying does. You revert to your true form if you die.

Level 15 -  You gain humanoid form. You can use your action to polymorph into a Small or Medium humanoid you have seen, or back into your true form. Your statistics, other than your size, are the same in each form. Any equipment you are wearing or carrying isn't transformed and you revert to your true form if you die. While in this form you can use your Bite and Claws attacks.

Once you transform this way you cannot do so again until you complete a short or long rest.