These magical items are said to be highly prized in the Underdark, and are rumored to have first been created by the Drow.  This hooded cloak is a very deep hued black.  They have elements of the Shadowfell and Plane of Shadow woven into the fibers.  Once the wearer has become attuned to the item, they understand the complete functionality of the cloak.  The passive elements include advantage on Stealth checks in dark or dimly lit conditions.  The wearer also gains the benefit of resistance against necrotic damage.  However, the drawbacks of the cloak are that the wearer has disadvantage on Stealth checks in well lit conditions, and is vulnerable to radiant damage.
The Cloak of Shadow also has a maximum of 7 charges, which enable the attuned wearer to enact the following spell-like abilities:

Shadow Step (2 charges)-allows the wearer to teleport from one shadow to another, similar to the Misty Step spell.  It allows the wearer, as a bonus action, to move up to 30 feet instantly, as long as they are moving from and to shadowed areas.  This power does not work in daylight. 

Shadow Bolt (3 charges)-as an action the wearer can send a bolt of necrotic 'shadow' energy towards a target within 60 feet.  The character must make a ranged attack roll.  A successful hit does 3d6 necrotic energy to the target.

Summon Shadow (5 charges)-as an action the wearer can summon a Shadow, as per the Monster Manual.  The summoned creature will be neutral in alignment, and will follow simple commands from the cloak wearer.  Once summoned the character must use a bonus action to command the Shadow during combat.  The summoned shadow will disappear after 1 minute.

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