Brimstone

choose a point within range. The area in a 50 foot sphere centered at that point noticeably reeks of sulfur. Any creature can make a intelligence saving throw against your spell save DC, on a success realizing the impending danger. each round that passes the sulfur smell gets even stronger.whenever you break concentration or the spell ends, the air in the sphere is set ablaze and all targets take fire damage equal to 2d4 plus 1d4 times the number of rounds that have passed since the spell was cast.a target can make a dexterity saving throw, taking half as much fire damage on a success.a creature that succeeded the intelligence saving throw has advantage on this save.

USING A HIGHER LEVEL SPELL SLOT: 
the fire damage increases by 3d4 for each slot level above 2.