I got this after updating from 1.2.0 to 1.3.1
Time: 2022-10-31 14:06:26 CST
Description: Exception in server tick loop
java.lang.NullPointerException
at mod.acgaming.extrasounds.sound.ESSoundManager.playSoundWorld(ESSoundManager.java:219)
at net.minecraft.entity.EntityLivingBase.handler$zih000$esPotionAddSound(EntityLivingBase.java:6089)
at net.minecraft.entity.EntityLivingBase.onNewPotionEffect(EntityLivingBase.java:809)
at net.minecraft.entity.EntityLivingBase.addPotionEffect(EntityLivingBase.java:751)
at shadows.deadly.gen.BossItem.initBoss(BossItem.java:121)
at shadows.deadly.gen.BossItem.place(BossItem.java:102)
at shadows.deadly.gen.BossFeature.generate(BossFeature.java:39)
at shadows.deadly.gen.WorldGenerator.terrainGen(WorldGenerator.java:41)
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler_2563_WorldGenerator_terrainGen_Pre.invoke(.dynamic)
at net.minecraftforge.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:90)
at net.minecraftforge.fml.common.eventhandler.EventBus.post(EventBus.java:182)
at net.minecraftforge.event.ForgeEventFactory.onChunkPopulate(ForgeEventFactory.java:769)
at net.minecraft.world.gen.ChunkGeneratorOverworld.populate(ChunkGeneratorOverworld.java:395)
at net.minecraft.world.chunk.Chunk.populate(Chunk.java:1019)
at net.minecraft.world.chunk.Chunk.populate(Chunk.java:999)
at net.minecraft.world.gen.ChunkProviderServer.provideChunk(ChunkProviderServer.java:157)
at net.minecraft.server.MinecraftServer.initialWorldChunkLoad(MinecraftServer.java:344)
at net.minecraft.server.integrated.IntegratedServer.loadAllWorlds(IntegratedServer.java:210)
at net.minecraft.server.integrated.IntegratedServer.init(IntegratedServer.java:233)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:486)
at java.lang.Thread.run(Unknown Source)
Suspected Mods: Extra Sounds (extrasounds), Apotheosis (apotheosis), Forge Mod Loader (FML), Minecraft Forge (forge)
Seems to be a conflict with Apotheosis, unfortunately the dev dropped support years ago.
https://mclo.gs/M185Beo