Celeste's Spear

You point your finger at a target within range and whisper a prayer. Seconds later, a beam of searing light descends from the heavens, splitting the earth asunder. The target takes 100 radiant damage. Subsequently, the area explodes with radiant energy in a 40ft radius sphere. Each creature of your choice in the area must make a charisma saving throw, taking 20d8 radiant damage on a failure, or half as much on a success. The initial target is excluded from this blast.
Finally, you may designate any number of allied creatures within the 40ft sphere; they recover an amount of hit points equal to 1d6 + your spellcasting modifier.