Source: Tal'Dorei Campaign Setting Reborn

Wondrous item, legendary (requires attunement by a non-good character)

When you don this circlet of gnarled onyx, black barbs dig into your head, imparting power to you as the circlet twists your appearance to amuse the Spider Queen. The current resting place of the Circlet of Barbed Vision is unknown, but rumor has it that a spectral assassin known as the Inevitable End seeks this relic.

Dormant. While the Circlet of Barbed Vision is in a dormant state, you have advantage on initiative rolls while you wear it, but your Charisma score decreases by 2. Your Charisma score returns to normal if you remove the circlet, but you take 4d6 psychic damage when you do so.

Additionally, when you make an attack roll, you can use your reaction to gain a +5 bonus to the roll. You make this choice after you see the roll, but before the GM says whether the attack hits or misses. You can’t use this property again until you finish a short or long rest.

Awakened. When the Circlet of Barbed Vision reaches an awakened state, you gain the following benefits:

• You have resistance to poison damage, and you are immune to the poisoned condition.
• Your ability to gain a bonus to an attack roll can be used twice between rests.

Exalted. When the Circlet of Barbed Vision reaches an exalted state, you gain the following benefits:

• You are immune to poison damage.
• You have truesight out to a range of 60 feet.
• Your ability to gain a bonus to an attack roll can be used three times between rests.