Hello!
I have a skyblock world which I made in 1.15.2 and have been upgrading it to the latest snapshots since 20w18a with no real issues.
However, ever since updating to 20w20a or higher (20b, 21a), the nether fortress I have in my world no longer spawns blazes or wither skeletons.
I do not really know why this is the case, as none of those snapshot releases should alter any nether generation behavior, but it clearly is happening. 20w18a and 20w19a still have the nether fortress functioning as it should, but any version above won't spawn blazes or wither skeletons.
If you would like any files, please let me know.
Kind regards,
Wester
Environment
Singleplayer server, Windows 10. Java version 8 update 241.
(Skyblock) Minecraft World generated on 1.15.2.
Thank you for your report!
However, this issue is a Duplicate of MC-184740.
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