You inscribe a volatile sigil of fire on the ground in a 5-foot square within range. The area ignites with magical flame for the duration. When a creature enters the sigil’s space for the first time on a turn or ends its turn there, it must make a Dexterity saving throw, taking 2d8 fire damage on a failed save, or half as much on a success.   The fire from the sigil does not spread and is harmless to objects or creatures outside its space.