Soul of Gwyn, Lord of Cinder

The  is a consumable item in Dark Souls, it is the souls of Gwyn, Lord of Cinder.

In-Game Description
Soul of Gwyn, Lord of Sunlight and Cinder, who linked the First Flame.

Lord Gwyn bequeathed most of his power to the Gods, and burned as cinder for the First Flame, but even so, Lord Gwyn's soul is a powerful thing indeed.