Cloak of Shadows

You rotate the Onyx gems in your hands while speaking the words of a spell to cause a shadow-like aura around 3 willing creatures of your choice that you can see (including yourself if you so choose). This shadowy aura coats itself around the creatures causing the creatures to be extremely dark as if they themselves were covered in darkness. 

A creature covered in this aura that is in Dim Light or Darkness has advantage on Dexterity (Stealth) and Any Creature that attacks an affected creature that is in Dim light or Darkness must attack at Disadvantage.

At Higher Levels: When you cast this spell using a spell slot of 2nd level or higher, you can target two additional creatures for each slot level above 1st. (You still need an Onyx Gem per person you are affecting)