dragon's wispers

Extend your hand with the dragon scale in it with your thumb, or equivalent, pointing in a direction. this creates a cone 30 by 5 feet that increases by 2.5 feet for each 5 feet away from you it is. Anything caught in the fire takes 3d6 fire damage, ignoring resistance or immunity to magical attacks. If targets are vulnerable to fire damage then they take an extra 1d6 fire damage. Things in the fire take a constitution saving throw to halve the damage from this attack, if they have resistance to fire damage they have advantage. If the dragon the scale used to cast this spell with has died the damage becomes necrotic. 

At higher levels: For each spell level above 3rd the spell range doubles until 5th and for each level above 3rd level the damage gets an extra 1d6, at level 5 the damage roll for this spell becomes d10 instead of d6