@janegei2n-beep

Checked for existing issues

• I have checked for existing issues, and have found none.

Tested latest version

• I have checked that this occurs on the latest version.

GregTech CEu Version

1.20.1-8.0.0 SNAPSHOT 84bb32e

Minecraft Version

1.20.1 Forge

Recipe Viewer Installed

None

Environment

Singleplayer

Cross-Mod Interaction

Yes

Other Installed Mods

• LowDragLib 1.0.40.b
• Only externally installed mod file in the mods folder: gtceu-1.20.1-8.0.0.jar
• Configuration 3.1.0

Expected Behavior

Whenever I try to install any mechanism from the mod, the game crashes.
The mod has been compiled from the latest update branch.

Actual Behavior

java.lang.AbstractMethodError: Receiver class com.gregtechceu.gtceu.api.machine.SimpleTieredMachine does not define or inherit an implementation of the resolved method 'abstract net.minecraft.world.level.Level getLevel()' of interface com.gregtechceu.gtceu.api.blockentity.IGregtechBlockEntity.
at com.gregtechceu.gtceu.api.blockentity.IGregtechBlockEntity.isRemote(IGregtechBlockEntity.java:46)
at com.gregtechceu.gtceu.api.machine.MetaMachine.isRemote(MetaMachine.java:901)
at com.gregtechceu.gtceu.api.machine.MetaMachine.subscribeServerTick(MetaMachine.java:238)
at com.gregtechceu.gtceu.api.blockentity.ITickSubscription.subscribeServerTick(ITickSubscription.java:23)
at com.gregtechceu.gtceu.api.machine.trait.NotifiableEnergyContainer.onMachineLoad(NotifiableEnergyContainer.java:111)
at com.gregtechceu.gtceu.api.machine.MetaMachine.onLoad(MetaMachine.java:173)
at com.gregtechceu.gtceu.api.machine.WorkableTieredMachine.onLoad(WorkableTieredMachine.java:117)
at com.gregtechceu.gtceu.api.machine.SimpleTieredMachine.onLoad(SimpleTieredMachine.java:96)
at net.minecraft.world.item.BlockItem.useOn(...)
at com.gregtechceu.gtceu.api.item.MetaMachineItem.useOn(...)

Steps to Reproduce

1. Start Minecraft 1.20.1 with Forge 47.4.13 and GTCEu 8.0.0.
2. Open a singleplayer world.
3. Try to place the GTCEu Simple Tiered Machine.
4. The client crashes immediately.

Additional Information

crash-2026年06月04日_19.39.53-client.txt

Environment
Minecraft version: 1.20.1
Mod loader: Forge 47.4.10 (as per crash report)
GregTech CEu version: gtceu-1.20.1-8.0.0.jar
Other mods:
LDLib 1.0.40.b
Configuration 3.1.0
(No other mods mentioned in the crash report)
Launcher: PrismLauncher
OS: Windows 11 (version 10.0) – but likely OS-independent
Java: OpenJDK 17.0.15 (Microsoft build)
Game type: Integrated singleplayer server
Language: Classical Chinese / Client language lzh in crash report – irrelevant
The crash report explicitly marks GregTech (gtceu) as the suspected mod.
The error is an AbstractMethodError – a runtime incompatibility. The class SimpleTieredMachine does not implement the abstract method getLevel() from IGregtechBlockEntity, even though the interface requires it.
The crash happens during onLoad() of the machine, specifically when NotifiableEnergyContainer tries to subscribe to server ticks.
This is likely a mod version inconsistency (maybe a broken build of GTCEu 8.0.0 or a missing update in the class hierarchy).
Similar issues have been reported in other GTCEu tickets (e.g. #2981, #2555) but with slightly different machine names.
Attached files (from the attachments folder):
crash-2026年06月04日_19.39.53-client.txt (full crash report)