Your GTNH Discord Username

No response

Mod Version

1.0.0-alpha56

Bug Report

When placing certain blocks added by the Flenix Cities mod (typically blocks with unusual, non-cube shapes such as slopes) with Angelica installed, the game will crash with a "chunk build failed" error. The world will then continue to crash with the same error on startup until Angelica is uninstalled. The crash log output is attached below:

crash-2025-08-19_01.03.49-client.txt

The crash can be reproduced with only Angelica and Flenix Cities installed and occurs regardless of whether shaders are enabled or not.

Java Version

Java 8

Graphics Card Vendor

NVidia

Shaders

No

MCPF or other features disabled by default

No: Go ahead and create an issue

Mod List or GTNH Pack Version

Angelica
Flenix Cities
GTNHLib

Final Checklist

• I have searched the issues and haven't found a similar issue.
• I have read the known incompatibilities and this is not related to one of those.
• I am running an officially released version. (Or, if I've compiled it myself I plan to fix the issue)