[MC-306893] Basalt pillars can again spawn inside of and replacing parts of nether fortresses

Steps to reproduce:

Generate a standard world with the seed “-6984174039507203179”.
Enter creative flight.

Execute

/execute in minecraft:the_nether run tp @s 617.37 71.38 -255.23 -404.70 34.35

Observed behavior:

A basalt pillar replaces parts of the wall of a nether fortress.

Expected behavior:

Basalt pillars should not replace parts of other structures.

This bug clones MC-171553.

Linked issues

duplicates 1

MC-186068 Basalt pillars can again spawn inside of and replacing parts of nether fortresses Reopened

Attachments

Comments 4

Automation for Jira 2026-03-15T16:05:41Z

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BugTracker_ 2026-03-15T17:25:25Z

I can confirm this in 1.21.11 as well. However, it seems like you’ve created the same bug report twice. Therefore, this ticket should be closed as a duplicate of MC-186068 . MC-186068 can then be reopened.

[Mod] ManosSef 2026-03-15T18:25:13Z

I've moved all the information from this ticket to MC-186068. Resolving this as a duplicate.

J Z 2026-03-15T18:39:42Z

They are actually not the same thing. I created MC-186068 after erroneously upgrading the world from a previous version. 20w22a is thus not an affected version for MC-186068 if this bug report is to be moved over there.