Necronic Damage - I Want to Turn Into a Giant Fucking Scorpion

You can't cast two spells in the same round as this. One of them is a cantrip, unfortunately. As my bonus action, I want to turn into a giant fucking scorpion. The yeddy goes and looks kind of taken aback and a little unnerved by what it sees in front of you. It turns around, coughs and looks up at you like it's vengeful.