The Potion of Decay cannot be crafted with a wither rose in the brewing stand.
Comments 4
You aren't supposed to use wither roses to brew potions of decay. They can only be found in cauldrons in witch huts.
Thank you for your report!
However, this issue is Working as Intended.
The report you have submitted is working as intended: Potion of Decay cannot be brewed and can only be obtained in cauldrons found in swamp huts.
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I don't think that recipe exists , because it's a newly added potion to the game and there is no recipe for it...