Polymer

Polymer

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[Bug] Crash when Polymer, Valkyrien Skies, and Supplementaries are used together (Fabric 1.20.1)

Closed this issue ยท 3 comments

commented

The game crashes upon world creation or joining when Polymer, Valkyrien Skies, and Supplementaries are present together. Removing any one of these three mods allows the game to load and play normally. This occurs on Fabric 1.20.1 with only the three mods (and their dependencies) present.

Mods involved (versions):

  • polymer-bundled 0.5.20+1.20.1
  • valkyrienskies-120-2.3.0-beta.7
  • supplementaries 1.20-3.1.34 and moonlight 1.20-2.14.11
Image

Crash report:
org.valkyrienskies.core.impl.util.assertions.stages.ConstraintFailedException: Constraints failed. Stages since last reset: [PRE_TICK, GET_LAST_TICK_CHANGES, UPDATE_CHUNKS, ...]
Required stages matching predicate in the following order: [PRE_TICK, oneOf[UPDATE_DIMENSIONS, UPDATE_BLOCKS, UPDATE_CHUNKS], POST_TICK_START, POST_TICK_GENERATED, POST_TICK_FINISH, CLEAR_FOR_RESET, UPDATE_PLAYERS]
at org.valkyrienskies.core.impl.util.assertions.stages.TickStageEnforcerImpl.stage(Unknown Source)
at org.valkyrienskies.core.impl.game.ships.ShipObjectServerWorld.setPlayers(Unknown Source)
at net.minecraft.server.MinecraftServer.handler$cpa000$valkyrienskies$preTick(MinecraftServer.java:5453)
...etc.

Steps to Reproduce:

  • Create a fresh Fabric 1.20.1 profile with only Polymer, Valkyrien Skies, and Supplementaries (plus dependencies).
  • Launch the game and create or join a world.
  • The game crashes every time, with the stacktrace above.
  • Removing any one of these three mods allows the game to load normally.

Notes:

  • All mods are the correct/latest versions for 1.20.1.
  • The issue occurs even with no other mods installed.
  • Seems to be a conflict involving world/dimension or entity handling.
  • Tested multiple times with different versions of the mods; crash is always reproducible.

Log and crash report:

latest.log

crash-2025-07-04_21.52.44-server.txt

commented

This seems to be an issue with supplementaries and/or VS more than anything, as it creates fake server world which it can't handle. Polymer might delay it a bit, which causes it to desync? Not sure. Best to report to other parties too (if you didn't do it already).

commented

This seems to be an issue with supplementaries and/or VS more than anything, as it creates fake server world which it can't handle. Polymer might delay it a bit, which causes it to desync? Not sure. Best to report to other parties too (if you didn't do it already).

Yes, I already reported it to others.