Crymson

You delve deep into the forbidden realm of blood magic, willing to pay the ultimate price for devastating power. As you cast this spell, you make a sacrificial offering of your own life force, drawing forth your essence in a surge of raw, dark energy. As you utter the incantation, a swirling vortex of dark red mist envelops your body. A beam of intense crimson light shoots from your hand, connecting to the heavens above, drawing upon your life force. Tormented faces materialize within the mist, reflecting the sacrifice you make. The mist expands in a shockwave, draining the life force of those caught within

Upon casting this spell, you take 10d10 necrotic damage on a failed Constitution Saving Throw, or half as much on a successful one. Every creature within a 30-foot radius centered on you, including yourself, must make a Constitution saving throw. On a failed save, a target takes 15d10 necrotic damage. On a successful save, the target takes half the necrotic damage.

Additionally, all creatures affected by the spell, including the caster, suffer from a severe life drain. Each creature's maximum hit points are reduced by the amount of necrotic damage they took from the spell. This reduction lasts until they complete a long rest and regain their lost hit points. If a target is killed by this, their body dissipates to nothing but a red pile of goo.