Tar and Feather

A creature you see within range much make a DEX saving throw or be covered in hot tar and feathers.

The target take 2D6 Fire Damage and an affected target’s Speed is halved, it takes a −2 penalty to AC and Dexterity saving throws, and it can’t take Reactions. On its turns, it can take either an action or a Bonus Action, not both, and it can make only one attack if it takes the Attack action. If it casts a spell with a Somatic component, there is a 25 percent chance the spell fails as a result of the target making the spell’s gestures too slowly. Additionally you can use your bonus action every round to apply 3d6 additional fire damage.

The target gets no additional saving throws, but a Dispel Magic or the if target taking damage from a fire spell using a spell slot of 4th level or higher will end the spell early.

If cast using a spell slot of 5th lvl or higher it adds an additional 1d6 damage to both the initial damage and the bonus action damage.