Book of Secrets

The Book of Secrets is a reward trophy obtained from the Keeper of Secrets in the Throne of Secrets area, after completing Abaddon's Gate, the final mission of the Nightfall campaign. You can only get one per character upon completing the mission for the first time, but you can trade with other players for more or pass it on to other characters.

Take it to one of the Keepers behind the Keeper of Secrets (Keeper of Scythes, Nature etc) to swap it for an unique item of your choice.

Collectors

 * Keeper of Shadows
 * Keeper of Steel
 * Keeper of the Elements
 * Keeper of Nature
 * Keeper of Light
 * Keeper of Bone
 * Keeper of Spirits
 * Keeper of Illusion
 * Keeper of the Scythe
 * Keeper of the Spear