Staff of Dunamancy

From Explorer's Guide to Wildemount, page 270.

Description
Staff, very rare (requires attunement by a wizard).

This staff of polished gray wood bears numerous runes carved along its length. The staff has 10 charges and regains 1d6 + 4 expended charges daily at dawn. If you expend the last charge, roll a d20. On a 1, the staff turns into dust and is destroyed.

While holding the staff, you can use an action to expend 2 or more of its charges to cast one of the following spells from it, using your spell save DC and spell attack bonus: Fortune's Favor (2 charges), Pulse Wave (3 charges), or Gravity Sinkhole (4 charges).

New Possibility. If you are holding the staff and fail a saving throw against a spell that targets only you, you can turn your failed save into a successful one. This property can't be used again until the next dawn.