The Thrysus - Sonic Staff

Quarterstaff +2 (Bard Focus) 7 charges.
Action: Expend 1 or more charges to cast the
Shatter or Thunderwave spell (save DC 16)
from it. For 1 charge, you cast the 2nd-level
version of the spell. You can increase the
spell slot level by one for each additional
charge you expend.
The staff regains 1d6 + 1 expended charges daily
at dawn. If you expend the staff's last charge,
roll a d20. On a 1, the staff crumbles into ashes
and is destroyed.