The staff has 5 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: Inflict Wounds (1 charge per level), or Shield (1 charge).

Additionally, you can expend 2 charges to add your proficiency bonus to the attacks and saves of allied undead within 10ft for 10 minutes, or touch the staff to an allied undead and heal them 1d6 per slot expended.

The staff regains 1d4 + 1 expended charges daily at dawn. 

Notes: Warlock of an Undead or Undying patron, Damage, Control, Combat, Warding