Biting Skull

You hurl a viciously gnashing skull at a creature you can see in range. The target must make a Dexterity saving throw. On a failure, they take 3d6 piercing damage and the skull latches on to them for 1 minute. While the skull remains attached to the target, they take 1 piercing damage at the start of each of their turns as the chattering skull gnaws at them. 

The target or another creature that can reach them can use their action to remove the skull.

At higher levels. When you cast this spell with a spell slot of 2nd level or higher, the initial damage increases by 1d6, and the gnawing damage increases by 1 for each level above 1st.