Mod Version:

DynamicSurroundings-1.16.4-4.0.1.1

Forge Version:

forge-1.16.4-35.1.13

--> Using this mod during the traveling in the Undergarden dimension cause world saving and exiting generating this issue:

`_java.lang.NullPointerException: Unexpected error
at org.orecruncher.environs.scanner.BiomeScanner.tick(BiomeScanner.java:86) ~[?:1.16.4-4.0.1.1] {re:classloading,pl:runtimedistcleaner:A}
at org.orecruncher.environs.handlers.BiomeSoundEffects.process(BiomeSoundEffects.java:85) ~[?:1.16.4-4.0.1.1] {re:classloading,pl:runtimedistcleaner:A}
at org.orecruncher.environs.handlers.Manager.onTick(Manager.java:119) ~[?:1.16.4-4.0.1.1] {re:classloading}
at org.orecruncher.environs.handlers.Manager.clientTick(Manager.java:133) ~[?:1.16.4-4.0.1.1] {re:classloading}
at net.minecraftforge.eventbus.ASMEventHandler_285_Manager_clientTick_ClientTickEvent.invoke(.dynamic) ~[?:?] {}
at net.minecraftforge.eventbus.ASMEventHandler.invoke(ASMEventHandler.java:85) ~[eventbus-3.0.5-service.jar:?] {}
at net.minecraftforge.eventbus.EventBus.post(EventBus.java:297) ~[eventbus-3.0.5-service.jar:?] {}
at net.minecraftforge.fml.hooks.BasicEventHooks.onPreClientTick(BasicEventHooks.java:105) ~[?:?] {re:classloading}
at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1414) ~[?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:mining_helmet.mixins.json:MinecraftMixin,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.Minecraft.func_195542_b(Minecraft.java:953) [?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:mining_helmet.mixins.json:MinecraftMixin,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:607) [?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:mining_helmet.mixins.json:MinecraftMixin,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.main.Main.main(Main.java:184) [?:?] {re:classloading,pl:runtimedistcleaner:A}
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_51] {}
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_51] {}
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_51] {}
at java.lang.reflect.Method.invoke(Method.java:497) ~[?:1.8.0_51] {}
at net.minecraftforge.fml.loading.FMLClientLaunchProvider.lambda$launchService$0(FMLClientLaunchProvider.java:51) [forge-1.16.4-35.1.13.jar:35.1] {}
at net.minecraftforge.fml.loading.FMLClientLaunchProvider$$Lambda$467/2075454833.call(Unknown Source) [forge-1.16.4-35.1.13.jar:35.1] {}
at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37) [modlauncher-8.0.6.jar:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:54) [modlauncher-8.0.6.jar:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:72) [modlauncher-8.0.6.jar:?] {}
at cpw.mods.modlauncher.Launcher.run(Launcher.java:82) [modlauncher-8.0.6.jar:?] {re:classloading}
at cpw.mods.modlauncher.Launcher.main(Launcher.java:66) [modlauncher-8.0.6.jar:?] {re:classloading}

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head --
Thread: Render thread
Stacktrace:
at org.orecruncher.environs.scanner.BiomeScanner.tick(BiomeScanner.java:86) ~[?:1.16.4-4.0.1.1] {re:classloading,pl:runtimedistcleaner:A}
at org.orecruncher.environs.handlers.BiomeSoundEffects.process(BiomeSoundEffects.java:85) ~[?:1.16.4-4.0.1.1] {re:classloading,pl:runtimedistcleaner:A}
at org.orecruncher.environs.handlers.Manager.onTick(Manager.java:119) ~[?:1.16.4-4.0.1.1] {re:classloading}
at org.orecruncher.environs.handlers.Manager.clientTick(Manager.java:133) ~[?:1.16.4-4.0.1.1] {re:classloading}
at net.minecraftforge.eventbus.ASMEventHandler_285_Manager_clientTick_ClientTickEvent.invoke(.dynamic) ~[?:?] {}
at net.minecraftforge.eventbus.ASMEventHandler.invoke(ASMEventHandler.java:85) ~[eventbus-3.0.5-service.jar:?] {}
at net.minecraftforge.eventbus.EventBus.post(EventBus.java:297) ~[eventbus-3.0.5-service.jar:?] {}
at net.minecraftforge.fml.hooks.BasicEventHooks.onPreClientTick(BasicEventHooks.java:105) ~[?:?] {re:classloading}
-- Affected level --
Details:
All players: 1 total; [ClientPlayerEntity['Andreadx_95'/166, l='ClientLevel', x=-3473.24, y=61.94, z=-1369.38]]
Chunk stats: Client Chunk Cache: 625, 399
Level dimension: undergarden:undergarden
Level spawn location: World: (8,64,8), Chunk: (at 8,4,8 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 119092 game time, 28270 day time
Server brand: forge
Server type: Integrated singleplayer server
Stacktrace:
at net.minecraft.client.world.ClientWorld.func_72914_a(ClientWorld.java:617) ~[?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,xf:OptiFine:default,xf:fml:xaeroworldmap:xaero_wm_clientworldclass,xf:fml:xaerominimap:xaero_clientworldclass,pl:mixin:APP:mixins.sndctrl.json:MixinClientWorld,pl:mixin:A}
at net.minecraft.client.Minecraft.func_71396_d(Minecraft.java:2024) [?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:mining_helmet.mixins.json:MinecraftMixin,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:628) [?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:mining_helmet.mixins.json:MinecraftMixin,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.main.Main.main(Main.java:184) [?:?] {re:classloading,pl:runtimedistcleaner:A}
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_51] {}
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_51] {}
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_51] {}
at java.lang.reflect.Method.invoke(Method.java:497) ~[?:1.8.0_51] {}
at net.minecraftforge.fml.loading.FMLClientLaunchProvider.lambda$launchService$0(FMLClientLaunchProvider.java:51) [forge-1.16.4-35.1.13.jar:35.1] {}
at net.minecraftforge.fml.loading.FMLClientLaunchProvider$$Lambda$467/2075454833.call(Unknown Source) [forge-1.16.4-35.1.13.jar:35.1] {}
at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37) [modlauncher-8.0.6.jar:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:54) [modlauncher-8.0.6.jar:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:72) [modlauncher-8.0.6.jar:?] {}
at cpw.mods.modlauncher.Launcher.run(Launcher.java:82) [modlauncher-8.0.6.jar:?] {re:classloading}
at cpw.mods.modlauncher.Launcher.main(Launcher.java:66) [modlauncher-8.0.6.jar:?] {re:classloading}_`

Single player or remote server?

Pushed 1.16.4-4.0.1.2 to CurseForge with a fix.