This band of stygian iron was forged in the depths of the Abyss at the behest of an ancient and nameless demon lord, to be given as a gift to one of his highest mortal champions.

While attuned to this ring, you gain resistance to necrotic damage.  You also gain darkvision out to a range of 60 feet, and your darkvision is not impeded by magical darkness.  You also gain telepathy with a range of 120 feet, but can only use it to communicate with demons, or another humanoid also attuned to an Abyssal Band of Shadows.

The ring can also bestow magical capabilities upon its wearer.  While wearing the ring you may cast invisibility once without expending a spell slot, targeting only yourself, regaining the ability to do so after completing a long rest.  Similarly, you may cast plane shift without expending a spell slot once per day, regaining the ability to do so daily at dawn.  This use of the spell can only transport you in and out of the Abyss.  When traveling to the Abyss, you may choose to arrive on any layer of the plane that you are familiar with.  Otherwise you will arrive on a random layer.  When leaving the Abyss, you travel to a familiar location on the plane of existence you most recently visited.

The ring also contains 5 charges, and regains 1d4 + 1 charges daily at dawn.  As a bonus action on your turn you may expend one of these charges to summon dark, shadowy flames to the hand wearing the ring.  The flames spread to cover one weapon held in that hand.  The next weapon attack you make using the burning weapon deals an additional 2d10 psychic damage on a hit.  The shadowy flames remain until the end of your next round, or until you land an attack and deal the bonus damage.

Notes: Resistance: Necrotic, Sense: Darkvision, Language: Telepathy, Damage: Psychic, Teleportation, Buff, Utility, Combat