Cloak of the shadowfell

This cloak is tattered with blood and ancient runes sown into the cloak. This cloak starts with 4 runes. A DC 17 history check will reveal that the runes are names of great powerful creatures and their will and duty to the wearer of this cloak. When you use the charge of this cloak you can enter the shadowfell plane for one action. While in the shadowfell plane you have the following bonuses:

• Your movement speed is double your normal speed or 75 feet, whichever is more.
• You can call upon the runes once per short/long rest and they will glow blood red and you can make a ranged attack (100ft). You have your proficiency bonus plus your dexterity modifier. If you hit you do 1d20 times the number of runes you have magical necrotic damage.
• You have Truesight for 100 feet.

You can earn runes by sparking the lives of the demons or devils that bow down to you (they will have the symbol of the abyss and will draw in blood a rune on the cloak). You have them at your will unless you command them to do something that will cause them physical, mental, and religious damage. This cloak allows you to understand anything a demon or devil has said and can talk back and communicate with it if the comment is directed at you by a devil or demon with the symbol of the abyss. 

Notes: Bonus: Stealth