crash from custom modpack. any help is appreciated!
cpw.mods.fml.common.LoaderException: java.lang.NoClassDefFoundError: gregtech/api/enums/ItemList
at cpw.mods.fml.common.LoadController.transition(LoadController.java:163)
at cpw.mods.fml.common.Loader.initializeMods(Loader.java:739)
at cpw.mods.fml.client.FMLClientHandler.finishMinecraftLoading(FMLClientHandler.java:311)
at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:552)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:878)
at net.minecraft.client.main.Main.main(SourceFile:148)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
at org.prismlauncher.launcher.impl.StandardLauncher.launch(StandardLauncher.java:88)
at org.prismlauncher.EntryPoint.listen(EntryPoint.java:126)
at org.prismlauncher.EntryPoint.main(EntryPoint.java:71)
Caused by: java.lang.NoClassDefFoundError: gregtech/api/enums/ItemList
at tb.common.block.BlockRainbowCactus.loadColors(BlockRainbowCactus.java:56)
at tb.init.TBBlocks.afterSetup(TBBlocks.java:345)
at tb.core.TBCore.init(TBCore.java:88)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at cpw.mods.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:532)
at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
at com.google.common.eventbus.EventBus.post(EventBus.java:275)
at cpw.mods.fml.common.LoadController.sendEventToModContainer(LoadController.java:212)
at cpw.mods.fml.common.LoadController.propogateStateMessage(LoadController.java:190)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
at com.google.common.eventbus.EventBus.post(EventBus.java:275)
at cpw.mods.fml.common.LoadController.distributeStateMessage(LoadController.java:119)
at cpw.mods.fml.common.Loader.initializeMods(Loader.java:737)
… 13 more
Caused by: java.lang.ClassNotFoundException: gregtech.api.enums.ItemList
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
… 42 more
Caused by: java.lang.NullPointerException