Pearl of Power

While this pearl is on your person, you can
use an action to speak its command word and
regain one expended spell slot. If the expended
slot was of 4th level or higher, the new slot is
3rd level. Once you use the pearl, it can't be
used again until the next dawn.
Nearly all men can stand adversity, but if you
want to test a man's character, give him power.