Gem of the Underdark

Gem of the Underdark Gem of the Underdark Adventuring Gear
  RARE Requires Attunement
  This gem has 7 charges. While holding this item, you may spend your action in order to expend 1 or more charges to do any of the following: You may cast any of the following spells through the item, requiring no components: darkness (2 charges, plus 1 additional charge for every level cast above 2nd), spider climb (2 charges), pass without trace (2 charges) darkvision (2 charges). For the next hour, you cannot become lost while travelling in the Underdark. You have advantage on any Wisdom (Survival) check made to locate something in the Underdark (1 charge). For the next hour, you gain a tremorsense and darkvision out to a range of 60 feet (2 charges). You and up to 4 willing creatures within 30 feet of you, teleport to a random unoccupied location in the Underdark, if you were not already in the Underdark. If you are already in the Underdark, you may instead teleport to an unoccupied entrance to the Underdark that you have physically visited before (1 charge per creature teleported, including yourself).
  This gem regains 1 charge for every 24 hours it spends in theUnderdark, up to a maximum of 7 charges.