focus of Cacophony

very rare (requires attunement by a bard, cleric, druid, sorcerer, or wizard)

This focus has 10 charges. While holding it, you can use an action to expend 1 or more of its charges to cast one of the following spells from it, using your spell save DC and spellcasting ability modifier: thunderwave (1 charge per level, up to 5 charges), shatter (1 charge per level, up to 5 charges), thunderlance (4 charges), or thunderous reprisal (4 charges, cast at level 4).

The focus regains 1d6 + 4 expended charges daily at dawn. If you expend the last charge, roll a d20. On a 1, the focus blackens, crumbles into cinders, and is destroyed.