Roblox Blox Fruits has a wide variety of fighting styles, all of which can be discovered in one of the many regions around the Seas. The Death Step fighting style, for example, can be learned by speaking with Phoeyu, the Reformed at one of two locations.
To learn the leg-based fighting style, you will need to have four things: 5,000 Fragments, 2,500,000 Beli, a Library Key (which accesses the Ice Castle), and the Dark Step style at level 400 of higher.
Once the criteria have been met, you can travel to Ice Castle, which is north of Dark Arena, in the Second Sea. From there, unlock the library, and speak with Phoeyu, the Reformed.
If you happen to miss Phoeyu when in the Second Sea, then you can find her again in the Castle on the Sea, which is located in the Third Sea. However, you will need to have unlocked the Ice Castle library before learning Death Step.
How to find the Library Key
The Library Key can be found in the main room of the Ice Castle. To get it, you will need to defeat the Awakened Ice Admiral. Note that the Library Key has a rare drop rate, averaging between 5% and 25%.
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