Burnout

Using the wizard’s own lifeforce as fuel, the caster can empower a number of spells per long rest equal to the proficiency bonus.

By spending one or more unused hit dice, the caster can empower a spell that requires the target to make a saving throw.

The empowered bonus damage is +1d6 per hit dice and of the same type as the spell itself. The bonus damage is subject to half damage as well.

The empowered spell can by either single target or multi target spell. In case of multi target spell, each target receives the bonus damage.

The caster can only fuel a spell with up to his proficiency bonus in bonus damage (d6’s) and max total bonus damage per long rest cannot be more than 6d6.