Darksiders II is parallel to the previous game. The Four Horsemen (War, Strife, Fury, and Death) are the last of the Nephilim, fusions of angels and demons who waged war on creation. To preserve the balance of the Universe, the Four, tired of conquest, received incredible powers from the Charred Council in exchange for slaughtering the rest of the Nephilim. The Horseman Death trapped the souls of his fallen brethren in an amulet, earning the title of Kinslayer, among others (though he kept its preservation a secret, since the Council ordered the Nephilim's souls destroyed).
While War is charged with his crimes, the horseman Death, sure that his brother is innocent, sets out on a personal mission to erase his brother's 'crime' and resurrect humanity. He first travels to the Icy Veil—a dimension between the three kingdoms of Heaven, Hell, and Earth—to seek the Keeper of Secrets for proof of War's innocence and the way to restore Earth.
The Keeper of Secrets, also known as the Crowfather, tells Death that he must go to the Tree of Life in order to restore humanity. The Crowfather, bitter about being given the Nephilim amulet (which torments him without end), refuses to let Death pass and attacks him in the shape of War. Death is thus forced to kill the Crowfather, but the Amulet shatters and embeds itself in his chest, knocking him out and sending him into a portal created by the Crowfather's death.