As they journey from cache to cache, the world itself begins to crumble, ash spewing forth in greater quantities, while the mists claim more people. As Vin and Elend struggle to consolidate the remaining outposts of humanity, they hunt the storage caches, seeking hints left by the Lord Ruler and the missing atium stash. The Lord Ruler, in preparation of such an event, created storage caches containing resources such as food and water in cave complexes beneath certain cities, each one providing directions to the next. He used his thousand years of imprisonment to plot his escape and the subsequent destruction he would reap. Freedom from the Well of Ascension enabled Ruin to directly affect the world more, increasing ashfall from the ashmounts and summoning earthquakes to break the world apart he could also influence people and control entire koloss armies. Ruin wanted to destroy the world instantaneously but his power was too weak, as part of it had been taken and hidden by the opposing force, Preservation, long ago. A thousand years later, the Mistborn Vin defeated the Lord Ruler and, tricked by the same prophecies, released the power from the Well of Ascension, freeing Ruin. Rashek then claimed the power for himself, remaking the world and forming the Final Empire which he ruled as the immortal Lord Ruler. Kwaan betrayed Alendi, instructing his nephew Rashek to kill him. If the Hero of Ages released the power as the prophecies claimed needed to be done, Ruin would be free to destroy the world. However, as Alendi's quest for the Well continued, Kwaan discovered that the Terris prophecies had been altered by a mysterious force called Ruin, whose power was contained within the Well. A thousand years before the fall of the Final Empire, the Terrisman Worldbringer Kwaan believed that he had found the Hero of Ages in Alendi, a blacksmith's son who rose to become the last ruler of Khlennium. The Hero of Ages is the prophesied savior of the Terris people, foretold to find and give up the power at the Well of Ascension, in a selfless act to save the world from the Deepness. It is preceded by The Well of Ascension in 2007 and followed by The Alloy of Law in the Mistborn: Era 2 series, Wax and Wayne in 2011.

It was published on October 14, 2008, by Tor Books and is the third novel in the Mistborn trilogy. Mistborn: The Hero of Ages is an epic fantasy novel written by American author Brandon Sanderson.

Mistborn the hero of ages