Gem of Seeing

Wondrous Item, Rare (Requires Attunement)

This gem has 3 charges. As a

When you take the Magic action, you cast a spell that has a casting time of an action or use a feature or magic item that requires a Magic action to be activated.

If you cast a spell that has a casting time of 1 minute or longer, you must take the Magic action on each turn of that casting, and you must maintain Concentration while you do so. If your Concentration is broken, the spell fails, but you don't expend a spell slot. See also Concentration.

action, you can expend 1 charge. For the next 10 minutes, you have

If you have Truesight, your vision is enhanced within a specified range. Within that range, your vision pierces through the following:

Darkness. You can see in normal and magical Darkness.

Invisibility. You see creatures and objects that have the Invisible condition.

Visual Illusions. Visual illusions appear transparent to you, and you automatically succeed on saving throws against them.

Transformations. You discern the true form of any creature or object you see that has been transformed by magic.

Ethereal Plane. You see into the Ethereal Plane.

out to 120 feet when you peer through the gem.

The gem regains 1d3 expended charges daily at dawn.

Source: Dungeon Master's Guide, p. 264