Source: Lost Mine of Phandelver and Phandelver and Below = The Shattered Obelisk

Staff, Rare (Requires Attunement by a Bard, Sorcerer, Warlock, or Wizard)

The top of this magic quarterstaff is shaped like a spider. It deals an extra 1d6 poison damage on a hit when used to make a weapon attack.

Spells. The staff has 10 charges. While holding it, you can expend the requisite number of charges to cast one of the following spells from the staff: Spider Climb (1 charge) or Web (2 charges, spell save DC 15).

The staff regains 1d6 + 4 expended charges daily at dusk. If you expend the staff’s last charge, roll a d20. On a 1, the staff crumbles to dust and is destroyed.