Conjure Minor Spirits

You conjure up to equal to 1 + your spellcasting ability modifier with a minimum of two minor spirits that are in your command, they can be finds, celestials, feys or elementals, those spirits you summon are incorporeal, fly around you, can´t take any type of actions and don´t have hit points, but the spirits are sentient, have memories from previous casts of this spell and know the same languages as the summoner. The spirits can be affected by the charmed condition and for the duration off the condition they are in the command of the charmer, for that case the original caster make the appropriate saving throw. 

If you have control over the spirits, you as a bonus action can use the magic of one spirit to make a spell ranged attack that deal 2d12 necrotic, radiant, psychic or force damage, depending on the type of the sentinel you summoned, to a creature within a 90ft of you and the sentinel disappear or You can use a reaction to reduce incoming damage by 2d12 to any creature, including you, within a radius of you by sacrificing a spirit to the attack.

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage and damage reduction increases by 1d12 for each slot level above 4th.