You ignite the ground in a 5-foot square space that you can see within range, creating a surface of fire. Any creature standing on the fire when you cast the spell must succeed on a Dexterity saving throw or take 1d8 fire damage. A creature must also make the saving throw when it moves into the fire’s space for the first time on a turn or ends its turn there. If the target is burning when it fails the saving throw for this spell, it instead takes 1d12 fire damage.   The fire ignites flammable objects in its area that aren’t being worn or carried. If you cast this spell again, any existing fire surface created by this spell fades.   This spell’s damage increases by one die when you reach 5th level (2d8 or 2d12), 11th level (3d8 or 3d12), and 17th level (4d8 or 4d12)