Dark Dilemma

You curse the names of your enemies, promising ruin upon them.

Choose a number of creatures within range equal to half your proficiency bonus. Two heralds of your patron appear before the creatures you choose, offering two fates to each of them as described below. When you cast this spell, choose from Fey, Fiend, Celestial, or Great Old One.

Annihilation. The creature's soul burns in a fiery explosion originating from within itself. Each creature within a 20 ft. radius sphere of the creature you choose takes 4d12 fire damage, and 4d12 damage based on the option you chose when you cast this spell - Radiant damage for Celestial, Psychic damage for Fey, Necrotic damage for Fiend, and Cold damage for Great Old One.

Doom. The chooser immediately dies if it has 100 hit points or less, or chooses to sacrifice an ally that it can see that is hostile to you of a challenge rating or level lower than its own - such an ally dies in its place. 

Each creature is dealt its fate in succession, based on who first answer telepathically. If a creature refuses to choose, its fate is determined by chance by flipping 1d2, choosing from the options above.