You launch a swirling violet orb from your tanzanite gem to a point you choose within range, whereupon it blossoms with a shrieking roar into an explosion of necrotic energy.

Each creature in a 15-foot-radius sphere centered on that point must make a Dexterity saving throw. A target takes 4d10 necrotic damage on a failed save, or half as much damage on a successful one. If a living creature is killed by this spell, a purple wisp of smoke drifts from the corpse carrying a part of its soul and trapping it within the tanzanite gem. The gem becomes charged and remains so until discharged. A charged gem can be discharged by casting the spell again but with one of three different effects listed below. 

-The spell can be cast again dealing double the amount of damage rolled.

-The spell can be cast again with double the radius.

-The spell can be cast again, granting temporary hit points to the caster equal to the damage rolled plus the spells level. 

 When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d10 for each slot level above 3rd.