Dome of Feathers

You clasp your hands together around a ravens feather, out of your hands shoot out a almost wall of feathers (color up to you) more and more feathers appear around you in a 10ft dome around you. Causing all light to go dark around you. All creatures that require sight while outside this dome have disadvantage on attacks against any creatures inside the dome. Those inside the dome also gain a plus 2 to there AC while inside the dome that the caster dictates, up to one friendly creature at one time. At higher spells slots, 4th lvl goes up to 3 extra AC, 5th lvl goes up to 4, 6th lvl goes up to 5, 7th lvl goes up to 6, 8th lvl goes up to 7 extra AC, 9th lvl goes up to 8 extra AC 

Creatures with true sight suffer no disadvantage to attacks.