Brimstone

You conjure a hunk of sulfuric brimstone that materializes in the air, then falls to the ground at a point within range. Any creature occupying that space must make a successful Dexterity saving throw or take [roll]2d8[/roll] bludgeoning damage.

The brimstone remains in the space where it fell while the spell persists. Each creature that starts its turn within 15 feet of the brimstone must make a successful Dexterity saving throw or take [roll]1d8[/roll] fire damage. The brimstone can be destroyed; it has an AC of 8 and 12 hp. The brimstone explodes if it takes fire damage; the explosion ends the spell and deals [roll]1d8[/roll] bludgeoning damage to all creatures within 15 feet, or half as much damage to a creature that makes a successful Dexterity saving throw.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, its fire damage increases by [roll]1d8[/roll] for each slot level above 1st.