Create Blood Droplet

You animate a portion of your own blood to act under your command. For every 4 hit points expended in the casting of this spell, you create a droplet of animated blood.  For every droplet created, the caster must make a Concentration Check in order to create another one. Upon a failure, the damage is taken to manifest another one of these without resulting in one of them and you may not create any more droplets on this turn, however, you do not lose concentration on the spell and any previously created droplets remain.  

These blood droplets are approximately the size of a golf ball each and move similarly to an ooze. On each of your turns, you may use a bonus action to mentally command any number of droplets to move as long as they remain within 120 feet of you. If a droplet would move out of this range, it instead will be instantly destroyed. These droplets have a speed of 15 feet and may climb walls and ceilings without needing a check. A droplet is destroyed if it attempts to travel through water, and droplets treat wet surfaces like difficult terrain. A droplet may be destroyed by taking any amount of damage, however, they are immune to Poison, Bludgeoning, Piercing, Slashing, and Psychic damage. A droplet destroyed does not detonate, and becomes an inert small pool of blood. A droplet may or may not leave behind a small trail of blood as they move at the discretion of the DM.

As an action on your turn, you may choose to see and hear from the location of one of your droplets until the end of your turn, becoming blinded and deafened to your own surroundings. Additionally, you may instead use your action to cause one or all of the droplets to explode in a burst of necrotic energy, destroying the droplet and damaging surrounding creatures. Each creature within 5 feet of a droplet must make a Dexterity saving throw. The creature takes 4d6 necrotic damage on a failed save, or half as much damage on a successful one.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage upon detonation increases by 1d6 for each slot level above 3rd.