Arcane Catastrophe

You create an arcane disaster. The options are listed below.

Abyssal Sinkhole: Requires the powdered horn of a Balor, worth 500 GP. Creates a gigantic hole 100 feet across in a circle and 100 feet deep. It opens a portal to the Abyss in the sinkhole.

Crystal Meteor: Requires a ball of crystal set on fire, worth 750 GP. Crashes a meteor that deals [roll]200d12[/roll] Radiant damage unaffected by Resistance or Immunity to all creatures in a 300 feet cube. Any objects in the cube are crystallized. If a creature is reduced to 0 hit points by this damage, they die and are turned into a Zombie which deals Radiant damage instead of any other damage as they are crystallized.

Skeleton Plague: Requires a bone coated in jade, worth 1,000 GP.  Unleashes a plague on up to 25 creatures you can see. Those creatures must make a DC 25 Constitution saving throw. On a fail, they are infected with the Skeleton Plague. They have 12 days left to live, and at the end of every second day, they gain a level of Exhaustion. They can repeat the save at the end of each second day with Disadvantage. On a success, they are freed from the disease. If a creature dies from this spell, they turn into a Skeleton which transmits the disease when they hit a creature with a Critical Hit. When an infected creature touches a creature, the creature touched must make a DC 15 Constitution saving throw or contract the disease.

Finally, the caster takes [roll]20d10[/roll] unspecified damage when it is cast. If this reduces the caster to 0 hit points, the caster is disintegrated, killing them.