Vulmon's mutation

You mutate your form into a horrid and powerful creature, fueled by your own life essence. Until the spell ends, you lose 1d6 hit points at the end of your turn, and you gain the following benefits: 

-Your size becomes large and your reach becomes 10 feet.

-You can make a melee spell attack as an action that deals 2d6 necrotic damage and heals you for the same amount.

-You grow leathery bat wings and have a flying speed equal to your walking speed.