A comet will shoot out of the wand, and begin to move fast in the direction you point your wand in. The longer it flies around, the more powerful it becomes. Your target must then make a Dexterity save with a DC of 20. On a hit, the target takes 1d10 damage, with an additional damage equal to how long the spell was flying around (concentration). After a round, all objects that can catch fire in the area where the comet travels near will begin to burn, and will effectively be burnt after 3 turns. If it is a type of armor that can burn, its AC will be dropped by one every turn, and once its AC drops below 10, it will be destroyed. The target must also take an action to put the fire out, else be dealt 2 points of fire damage until the fire is put out.
Spell Level Upgrade. The damage increases by 1d10 when you reach levels 5 (2d10), 11 (3d10), and 17 (4d10).