"Let go and scream Tatsumi with all the fire in you soul!!!!"
― Bulat (Akame ga Kill)
The ability to possess an uncommonly potent soul and gain highly formidable abilities as a result of the soul's power.
User has a strong soul that is equivalent to the power of many souls which comes in handy in situations that tests one's spiritual fortitude and grants spiritual abilities. The user's soul is unable to be bound by anything and lives free without anything holding it back. It is also strengthened by the user's desire to get what they want, no matter the cost.
Asura (Asura's Wrath) has a strong enough soul to escape the depth of Naraka.
Dante Alighieri (Dante's Inferno) possessed a strong enough soul to defeat Death and traverse all nine circles of Hell to save his wife, Beatrice.
When the first flame was lit, the Furtive Pygmy (Dark Souls) obtained the Dark Soul, passing it down through its descendants as Humanity.
When the first flame was lit, Gwyn, Lord of Sunlight (Dark Souls) obtained the Lord Soul of Light, using such power to fight against the dragons and become a god to the new world.
When the first flame was lit, Gravelord Nito (Dark Souls) obtained the Lord Soul of Death, using such power to fight against the dragons and become a god to the new world.
When the first flame was lit, the Witch of Izalith (Dark Souls) obtained the Lord Soul of Life, using such power to fight against the dragons and become a god of the new world.
Kratos' (God of War) soul is powerful enough to escape the Underworld more than once.
Issei Hyoudou (Highschool DxD) possesses a will strong enough to keep him pushing towards his limits and is powered by his perverted mind.
Kazuma and Ryuho (s-CRY-ed) possess a strong, independent spirit, driven by their need live without being controlled by anyone or anything. This in turn allowed them to gain control of their own destinies and aquire a great deal of Alter power.
Witch Souls (Soul Eater) are known to hold great power, making them a sought after prize to meister, weapon and kishin alike.
Prometheus, Zeus and Napoleon (One Piece) were created from Linlin's own soul, making them the strongest homies.
Frisk's (Undertale) soul is matched and fueled with determination.