Devastation beam

Once the user starts the spell they put their hands close together and start to form the destructive energy in their hands if the caster is hit with any damage they must make a Wisdom saving throw DC 19 to control the destructive energy on a fail this orb of destruction runs wild and fire 10 black and red pulsating beams all creatures including the caster in a 30 foot area take 15d6 necrotic damage But if the caster succeeds the saving throw then on the beginning of their 3 turn the caster can point their hands and target up to four creatures when they unleash the distractive magic a large black and red pulsating Beam that splits into four smaller ones follows the target when the beam gets close to the target must make a dexterity saving throw on a successful save the target takes half damage but on a fail the target takes 31d6 necrotic damage and if the target as lower then a 100 hp the target drops to 0 hp and the targets are obliterated and a massive explosion covers everything in a 50 ft area in black smoke additionally any healing magic that is casted in the 50 ft zone has no effect for the energy's of the beam eat away at any and all healing magic.