Combustion
Casting Time: 1 action
Range: Self (60-foot radius)
Components: V, S
Duration: Instantaneous
Classes: Paladin
A paladin calls in every last ember of their oath at once. Light gathers under the skin until it has nowhere left to go, and it doesn't so much erupt outward as it does escape — a 60-foot sphere of radiant fire that scorches ally, enemy, and caster alike. Nothing about this spell holds anything back, including from you.
Roll 3d12 + your spell attack bonus, radiant damage. Every creature within 60 feet of you, including yourself, takes this damage. Each other creature in range must make a Dexterity saving throw, taking half damage on a success. You do not get a saving throw — you automatically take half the damage rolled, rounded down.
The Price.
This spell does not require you to expend a spell slot in the usual
way. Instead, casting it expends every spell slot you currently have,
of every level, all at once. Immediately after the damage resolves,
your Hit Point maximum is permanently reduced by 1d10 + your spell
attack bonus, and you gain the Incapacitated condition for 4 rounds.