Alchemist fire.
1d4 fire damage on contact and 1d4 fire damage on the start of each of their turns.

Or, get 20 vials of alchemist fire and bundle them up. 20d4 fire damage and 20d4 fire damage per turn

Smart

Its wizard time motha f**ka, F i r e b a l l

it's sicience time motha f**ka, G R E E K F I R E

alchemy mother f**ka

fireball