Wand of Fireballs

Requires attunement by a spellcaster.
Holds 7 charges. If one charge is spent, deal 8D6 fire damage (DC 15) to all within range. Deal 1D6 extra for each additional charge spent.
Regains 1D6+1 charges each dawn.
If the charges ever reach zero, roll a D20. On a 1, the wand crumbles to dust.