Lost Lore

Lost Lore is a game mode in Fire Emblem Heroes.

Overview
The player is tasked with sending their Heroes to various worlds based on the Fire Emblem series in order to restore their plotlines, by recovering the world's "Lore Lines". Heroes are sent to various locations based on the game and the specific plotline. Heroes from that game's world will recieve additional Lore Lines.

Once all the Lore Lines are acquired, the player must partake in a Strike, in which a team of four Heroes must fight against a group of enemies from that game. Once this has been fulfilled, a plot summary of the game's events will appear, completing the mode.

White Rose and Sable Knight
Set in the World of Mystery (based on Fire Emblem: Shadow Dragon and the Blade of Light, Fire Emblem: Mystery of the Emblem, and their remakes), the Strike enemies are Camus, Lorenz, and two Sable Knights.

One of True Sight
Set in the World of Blades (based on Fire Emblem: The Binding Blade and Fire Emblem: The Blazing Blade), the Strike enemies are Narcian, Windham, and two Bern Soldiers.

The Martyr Exalt
Set in the World of Awakening (based on Fire Emblem Awakening), the Strike enemies are Gangrel, Mustafa, a Plegian, and a Risen.

Trivia

 * Lorenz, Windham, Gangrel, and Mustafa all made their Fire Emblem Heroes debuts through their appearances as Strike enemies, rather than as playable characters.