Horn of Valere
From A Wheel of Time Wiki
The Horn of Valere is a powerful artifact. Little is known of how it works, but the effect is clear: when the Horn is sounded, the great heroes of the Pattern are summoned to battle, and will serve whoever blew the horn.
The Horn's origins are uncertain, but it was lost to the world and faded into the realm of myth for hundreds of years. Illian traditionally mounted "Great Hunts" for the Horn in which men and women from all over the world would gather and go out in search, but all were unsuccessful.
The Horn resurfaced recently at the Eye of the World. It was kept safe until later sounded at Falme by Mat Cauthon during a Seanchan invasion. It became apparent that the Horn, once sounded, links with the sounder and from then on will work for none but the original blower as long as he lives.
The Horn of Valere is supposed to be present at the Last Battle, but there is no mention of it in the Prophecies of the Dragon.
