Soulfire

Soulfire is the ability to use the soul as a power-boost in magic, affiliated with heaven and given to Harry Dresden. It is the antithesis to Hellfire, which Harry lost when the Shadow of Lasciel (Lash) was erased from his subconscious mind at the end of Proven Guilty. Soulfire has manifested as a silvery ghost of Harry's force spell, and a blue-white supercharged version of his fire blast. Bob commented that it used part of the human soul, which regenerates over time and through acts which are "good for the soul," but will kill the user if it is completely drained.