Up to 1 minute
This spell creates a sphere centered on a point within in range. The sphere can have a radius up to 40 feet. The area is filled with magical darkness and crushing gravitational force.
For the duration, the area is difficult terrain. A creature with darkvision can't see through the magical darkness, and nonmagical light can't illuminate it. No sound can be created within or pass through the area. Any creature/object inside the sphere is immune to thunder dmg, and are deafened while entirely inside it. Casting a spell with a verbal component is impossible there.
Any creature that enters the spell's area for the first time on a turn or starts its turn there must make a Con saving throw. The creature takes 8d10 force damage on a failed save, or half as much damage on a success. A creature reduced to 0 hit points by this damage is disintegrated. A disintegrated creature and everything it is wearing and carrying, except magic items, are reduced to a pile of dust.
shard of onyx and a drop of the caster's blood (both consumed)