The Fleshcraft Hydra, also referred to as simply Hydra, is a World Boss in Diablo Immortal tied to a Zone Event known as "Kulle's Hidden Chambers." This event occurs daily within the Library of Zoltun Kulle, the zone directly north of the Shassar Sea. However, before adventurers can participate in this "Kulle's Hidden Chambers," they must first reach Hell I. For those unfamiliar, Hell I through IV are the gameplay mutators that modify the difficulty of Diablo Immortal. As players progress through the end-game content by raising their Paragon Levels and Monster Combat Rating, they will have access to higher levels of Hell.
Hell I in Diablo Immortal requires heroes to complete the main campaign and reach Level 60, after which they can alter the game's difficulty by selecting the «skull icon» within the screen for Westmarch's map. Once this is done, fast travel to the Library of Zoltun Kulle to get started on participating in "Kulle's Hidden Chambers."
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The primary objective of "Kulle's Hidden Chambers" is for players to "Collect Lost Pages in the Library of Zoltun Kulle." More specifically, adventurers must find and gather five Lost Pages to open Portal Tomes that grant access to Kulle's Hidden Chambers. Whenever a Portal Tome is opened, there's a chance for the Fleshcraft Hydra or the Sandstone Golem to spawn on the map in Diablo Immortal. Due to this RNG mechanic, attempting to summon the Hydra while doing the event solo might take a while. Therefore, it's best to complete "Kulle's Hidden Chambers" with many other players, as they also have a chance to summon the World Boss.
Lost Pages appear on the ground as shiny golden sheets of paper that spawn
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