Don's Magic Stone

You touch up to three pebbles and imbue them with magic. You or someone else can make a ranged spell attack with one of the pebbles by throwing it or hurling it with a sling. If thrown, it has a range of 60 feet and 120 feet if hurled with a sling. If someone else attacks with the pebble, that attacker adds your spellcasting ability modifier, not the attacker’s, to the attack roll. On a hit, the target takes bludgeoning damage equal to 1d6 + your spellcasting ability modifier, if used as sling ammunition the damage die for the spell increases from 1d6 to 1d8. The stone is considered magical for the purpose of overcoming resistance. Hit or miss, the spell then ends on the stone.

This spell's damage increases by 1d6/1d8 when you reach 5th level (2d6/2d8), 11th level (3d6/3d8), and 17th level (4d6/4d8).

If you cast this spell again, the spell ends early on any pebbles still affected by it.