Boss Rush Mode

Boss Rush Mode is a mode introduced in some later games and is accessible once the game is completed (some require the "Best Ending" to be recieved) or by killing all bosses (in Curse of Darkness and Lament of Innocence's case).

Appearance in Lament of Innocence
In LoI, Boss Rush Mode is unlocked once all bosses are defeated (including the Elementals and Forgotten One). It then appears in the Castle Entrance as a sixth portal.

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