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Each boss has a special Legendary Weapon to which they are especially vulnerable. Often, these weapons are hidden in another realm and are typically not found until much later in the game. Because they don't significantly impact the difficulty of a boss and they can only be used once (you must retrieve the weapon again if you want to use it), they are usually ignored until the boss can be defeated through conventional means. For instance, the Lich is the boss of the first realm, the Forsaken Province, and the first that the player can battle. However, the Legendary Weapon to which he is most vulnerable, the Good Book, isn't found until the Sky Domain, the fourth realm. By the time players retrieve the Legend Item, they are much more prepared to go back and defeat the Lich.

The console version of the game allows players to skip fighting boss characters on their first play through a realm. This allows them to progress through the game and become stronger before facing off against a boss, as even with a Legend Item these foes are extremely tough.

The Legend Items, the boss they apply to, and where they can be found are:

Legend	Used Against	Found In	Effect
Parchment of Fire	Ice Boss (Yeti)	Haunted Cemetery, Forsaken Province	Creates a wall of fire to counter the Yeti's ice attacks.
Javelin of Blinding	Sky Boss (Plague Fiend)	Lost Cave, Mountain	Stabs the Plague Fiend's one eye and reduces his accuracy.
Ice Axe	Mountain Boss (Dragon)	Castle Barracks, Castle Realm	Freezes the Dragon solid.
Good Book (a.k.a. the Book of Protection)	Province Boss (Lich)	Sky Shipyards, Sky Realm	Shoots a ball of light and slows down the Lich with holy flames.
Scimitar of Decapitation	Castle Boss (Chimera)	Gnarled Branches, Forest Realm	Beheads the Chimera's lion head, significantly damaging the beast.
Toxic Bellows	Forest Boss (Spider Queen)	Mystic Pyramid, Desert Land	Reduces the Spider Queen's size and power.
Lamp of Dark Obstruction	Desert Boss (Genie)	Erupting Fissure, Ice Domain	Creates a dark cloud to blind the Genie.
Lantern of Revelation	Dream Boss (Shadow Wraith)	Haunted Grounds, Dream World	Blocks all of the Shadow Wraith's shadow attacks with its superior light.
Soul Savior	Skorne (First Encounter in the Desecrated Temple)	Desecrated Temple	Deflects Skorne's attacks right back; found and used in the Desecrated Temple.