Mob Spawning Issue

        1: net.minecraftforge.eventbus.EventBus$$Lambda$3068/0x0000000100b8cc40@416b681c
java.lang.UnsupportedOperationException
    at com.google.common.collect.ImmutableCollection.add(ImmutableCollection.java:218)
    at mod.trianglesinpoo.mcores.oregen.generateOres(oregen.java:36)
    at net.minecraftforge.eventbus.EventBus.doCastFilter(EventBus.java:247)
    at net.minecraftforge.eventbus.EventBus.lambda$addListener$11(EventBus.java:239)
    at net.minecraftforge.eventbus.EventBus.post(EventBus.java:302)
    at net.minecraftforge.eventbus.EventBus.post(EventBus.java:283)
    at net.minecraftforge.common.ForgeHooks.enhanceBiome(ForgeHooks.java:944)
    at net.minecraft.world.biome.Biome.lambda$static$8(Biome.java:75)
    at com.mojang.datafixers.util.Function8.lambda$null$6(Function8.java:22)
    at com.mojang.datafixers.util.Function4.lambda$null$2(Function4.java:14)
    at com.mojang.serialization.DataResult$Instance.ap2(DataResult.java:315)
    at com.mojang.datafixers.kinds.Applicative.ap4(Applicative.java:84)
    at com.mojang.serialization.codecs.RecordCodecBuilder$Instance$7.decode(RecordCodecBuilder.java:404)
    at com.mojang.serialization.codecs.RecordCodecBuilder$2.decode(RecordCodecBuilder.java:107)
    at com.mojang.serialization.MapDecoder.lambda$compressedDecode$0(MapDecoder.java:52)
    at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
    at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
    at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
    at com.mojang.serialization.MapDecoder.compressedDecode(MapDecoder.java:52)
    at com.mojang.serialization.MapCodec$MapCodecCodec.decode(MapCodec.java:91)
    at com.mojang.serialization.Decoder.parse(Decoder.java:18)
    at net.minecraft.util.registry.WorldSettingsImport$IResourceAccess$RegistryAccess.parseElement(WorldSettingsImport.java:236)
    at net.minecraft.util.registry.WorldSettingsImport.readAndRegisterElement(WorldSettingsImport.java:131)
    at net.minecraft.util.registry.WorldSettingsImport.lambda$decodeElements$5(WorldSettingsImport.java:105)
    at com.mojang.serialization.DataResult.lambda$flatMap$10(DataResult.java:138)
    at com.mojang.datafixers.util.Either$Left.map(Either.java:38)
    at com.mojang.serialization.DataResult.flatMap(DataResult.java:136)
    at net.minecraft.util.registry.WorldSettingsImport.decodeElements(WorldSettingsImport.java:104)
    at net.minecraft.util.registry.DynamicRegistries.readRegistry(DynamicRegistries.java:144)
    at net.minecraft.util.registry.DynamicRegistries.load(DynamicRegistries.java:132)
    at net.minecraft.util.registry.WorldSettingsImport.create(WorldSettingsImport.java:53)
    at net.minecraft.util.registry.DynamicRegistries.builtin(DynamicRegistries.java:85)
    at net.minecraft.client.Minecraft.loadLevel(Minecraft.java:1681)
    at net.minecraft.client.gui.screen.WorldSelectionList$Entry.loadWorld(WorldSelectionList.java:364)
    at net.minecraft.client.gui.screen.WorldSelectionList$Entry.joinWorld(WorldSelectionList.java:273)
    at net.minecraft.client.gui.screen.WorldSelectionList$Entry.mouseClicked(WorldSelectionList.java:225)
    at net.minecraft.client.gui.widget.list.AbstractList.mouseClicked(AbstractList.java:309)
    at net.minecraft.client.gui.INestedGuiEventHandler.mouseClicked(INestedGuiEventHandler.java:28)
    at net.minecraft.client.MouseHelper.lambda$onPress$0(MouseHelper.java:87)
    at net.minecraft.client.gui.screen.Screen.wrapScreenError(Screen.java:427)
    at net.minecraft.client.MouseHelper.onPress(MouseHelper.java:85)
    at net.minecraft.client.MouseHelper.lambda$setup$4(MouseHelper.java:175)
    at net.minecraft.util.concurrent.ThreadTaskExecutor.execute(ThreadTaskExecutor.java:86)
    at net.minecraft.client.MouseHelper.lambda$setup$5(MouseHelper.java:174)
    at org.lwjgl.glfw.GLFWMouseButtonCallbackI.callback(GLFWMouseButtonCallbackI.java:36)
    at org.lwjgl.system.JNI.invokeV(Native Method)
    at org.lwjgl.glfw.GLFW.glfwPollEvents(GLFW.java:3101)
    at com.mojang.blaze3d.systems.RenderSystem.flipFrame(RenderSystem.java:89)
    at net.minecraft.client.MainWindow.updateDisplay(MainWindow.java:305)
    at net.minecraft.client.Minecraft.runTick(Minecraft.java:996)
    at net.minecraft.client.Minecraft.run(Minecraft.java:607)
    at net.minecraft.client.main.Main.main(Main.java:184)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:564)
    at net.minecraftforge.userdev.FMLUserdevClientLaunchProvider.lambda$launchService$0(FMLUserdevClientLaunchProvider.java:52)
    at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37)
    at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:54)
    at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:72)
    at cpw.mods.modlauncher.Launcher.run(Launcher.java:82)
    at cpw.mods.modlauncher.Launcher.main(Launcher.java:66)
    at net.minecraftforge.userdev.LaunchTesting.main(LaunchTesting.java:105)

When adding mob spawing with the following code i get the error above 

				biome.getMobSettings().getMobs(EntityClassification.MONSTER).add(new MobSpawnInfo.Spawners(ModEntityTypes.MITE.get(),100,1,3));

Edited May 6, 20214 yr by eggpasta
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