True Life Siphon

Placing one hand on your chest and another on an ally you can touch, you can channel all of your life force into their own. You take Necrotic damage equal to all of your hit points, dropping you to 0, and you restore the ally's hit points by a full amount equal to the damage you took. You can, acting as a bridge between, also do the same between two allies; placing one hand on each. The Necrotic damage ignores resistances and immunity.