On my modded server a friend has a crash every time he attacks Barako in the beginning then when he relogs everything is fine. He has fought two Barakos and has had the same issue everytime.

---- Minecraft Crash Report ----
// You should try our sister game, Minceraft!

Time: 5/11/21 12:06 PM
Description: Ticking entity

java.lang.NullPointerException: Ticking entity
at com.bobmowzie.mowziesmobs.server.entity.barakoa.EntityBarako.func_70071_h_(EntityBarako.java:317) ~[?:1.5.16] {re:classloading}
at net.minecraft.client.world.ClientWorld.func_217418_a(ClientWorld.java:192) ~[?:?] {re:mixin,pl:runtimedistcleaner:A,re:classloading,xf:fml:xaerominimap:xaero_clientworldclass,pl:mixin:APP:abnormals_core.mixins.json:client.ClientWorldMixin,pl:mixin:APP:mixins.sndctrl.json:MixinClientWorld,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.world.ClientWorld$$Lambda$18406/803537446.accept(Unknown Source) ~[?:?] {}
at net.minecraft.world.World.func_217390_a(World.java:554) ~[?:?] {re:computing_frames,pl:accesstransformer:B,re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:create.mixins.json:TileWorldHookMixin,pl:mixin:A}
at net.minecraft.client.world.ClientWorld.func_217419_d(ClientWorld.java:161) ~[?:?] {re:mixin,pl:runtimedistcleaner:A,re:classloading,xf:fml:xaerominimap:xaero_clientworldclass,pl:mixin:APP:abnormals_core.mixins.json:client.ClientWorldMixin,pl:mixin:APP:mixins.sndctrl.json:MixinClientWorld,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1483) ~[?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:betterendforge.mixins.json:MinecraftMixin,pl:mixin:APP:create.mixins.json:ShaderCloseMixin,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:betterendforge.mixins.json:MinecraftMixin,pl:mixin:APP:create.mixins.json:ShaderCloseMixin,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:betterendforge.mixins.json:MinecraftMixin,pl:mixin:APP:create.mixins.json:ShaderCloseMixin,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-1.16.5-36.1.16.jar:36.1] {}
at net.minecraftforge.fml.loading.FMLClientLaunchProvider$$Lambda$477/854255346.call(Unknown Source) [forge-1.16.5-36.1.16.jar:36.1] {}
at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37) [modlauncher-8.0.9.jar:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:54) [modlauncher-8.0.9.jar:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:72) [modlauncher-8.0.9.jar:?] {}
at cpw.mods.modlauncher.Launcher.run(Launcher.java:82) [modlauncher-8.0.9.jar:?] {re:classloading}
at cpw.mods.modlauncher.Launcher.main(Launcher.java:66) [modlauncher-8.0.9.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 com.bobmowzie.mowziesmobs.server.entity.barakoa.EntityBarako.func_70071_h_(EntityBarako.java:317) ~[?:1.5.16] {re:classloading}
at net.minecraft.client.world.ClientWorld.func_217418_a(ClientWorld.java:192) ~[?:?] {re:mixin,pl:runtimedistcleaner:A,re:classloading,xf:fml:xaerominimap:xaero_clientworldclass,pl:mixin:APP:abnormals_core.mixins.json:client.ClientWorldMixin,pl:mixin:APP:mixins.sndctrl.json:MixinClientWorld,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.world.ClientWorld$$Lambda$18406/803537446.accept(Unknown Source) ~[?:?] {}
-- Entity being ticked --
Details:
Entity Type: mowziesmobs:barako (com.bobmowzie.mowziesmobs.server.entity.barakoa.EntityBarako)
Entity ID: 325909
Entity Name: Barako, the Sun Chief
Entity's Exact location: -5352.50, 73.50, -3210.50
Entity's Block location: World: (-5353,73,-3211), Chunk: (at 7,4,5 in -335,-201; contains blocks -5360,0,-3216 to -5345,255,-3201), Region: (-11,-7; contains chunks -352,-224 to -321,-193, blocks -5632,0,-3584 to -5121,255,-3073)
Entity's Momentum: 0.00, 0.00, 0.00
Entity's Passengers: []
Entity's Vehicle: ERROR NullPointerException: null
Stacktrace:
at net.minecraft.world.World.func_217390_a(World.java:554) ~[?:?] {re:computing_frames,pl:accesstransformer:B,re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:create.mixins.json:TileWorldHookMixin,pl:mixin:A}
at net.minecraft.client.world.ClientWorld.func_217419_d(ClientWorld.java:161) ~[?:?] {re:mixin,pl:runtimedistcleaner:A,re:classloading,xf:fml:xaerominimap:xaero_clientworldclass,pl:mixin:APP:abnormals_core.mixins.json:client.ClientWorldMixin,pl:mixin:APP:mixins.sndctrl.json:MixinClientWorld,pl:mixin:A,pl:runtimedistcleaner:A}

-- Affected level --
Details:
All players: 1 total; [ClientPlayerEntity['greenguy1234'/244785, l='ClientLevel', x=-5351.78, y=70.00, z=-3203.34]]
Chunk stats: Client Chunk Cache: 729, 483
Level dimension: minecraft:overworld
Level spawn location: World: (253,64,188), Chunk: (at 13,4,12 in 15,11; contains blocks 240,0,176 to 255,255,191), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 4139141 game time, 4775211 day time
Server brand: forge
Server type: Non-integrated multiplayer server
Stacktrace:
at net.minecraft.client.world.ClientWorld.func_72914_a(ClientWorld.java:447) ~[?:?] {re:mixin,pl:runtimedistcleaner:A,re:classloading,xf:fml:xaerominimap:xaero_clientworldclass,pl:mixin:APP:abnormals_core.mixins.json:client.ClientWorldMixin,pl:mixin:APP:mixins.sndctrl.json:MixinClientWorld,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.Minecraft.func_71396_d(Minecraft.java:2029) [?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:betterendforge.mixins.json:MinecraftMixin,pl:mixin:APP:create.mixins.json:ShaderCloseMixin,pl:mixin:A,pl:runtimedistcleaner:A}
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:623) [?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:betterendforge.mixins.json:MinecraftMixin,pl:mixin:APP:create.mixins.json:ShaderCloseMixin,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-1.16.5-36.1.16.jar:36.1] {}
at net.minecraftforge.fml.loading.FMLClientLaunchProvider$$Lambda$477/854255346.call(Unknown Source) [forge-1.16.5-36.1.16.jar:36.1] {}
at cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37) [modlauncher-8.0.9.jar:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:54) [modlauncher-8.0.9.jar:?] {}
at cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:72) [modlauncher-8.0.9.jar:?] {}
at cpw.mods.modlauncher.Launcher.run(Launcher.java:82) [modlauncher-8.0.9.jar:?] {re:classloading}
at cpw.mods.modlauncher.Launcher.main(Launcher.java:66) [modlauncher-8.0.9.jar:?] {re:classloading}

-- System Details --
Details:
Minecraft Version: 1.16.5
Minecraft Version ID: 1.16.5
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1375691080 bytes (1311 MB) / 4175953920 bytes (3982 MB) up to 4175953920 bytes (3982 MB)
CPUs: 6
JVM Flags: 5 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx4096m -Xms256m -XX:PermSize=256m
ModLauncher: 8.0.9+86+master.3cf110c
ModLauncher launch target: fmlclient
ModLauncher naming: srg
ModLauncher services:
/mixin-0.8.2.jar mixin PLUGINSERVICE
/eventbus-4.0.0.jar eventbus PLUGINSERVICE
/forge-1.16.5-36.1.16.jar object_holder_definalize PLUGINSERVICE
/forge-1.16.5-36.1.16.jar runtime_enum_extender PLUGINSERVICE
/accesstransformers-3.0.1.jar accesstransformer PLUGINSERVICE
/forge-1.16.5-36.1.16.jar capability_inject_definalize PLUGINSERVICE
... (134 lines left)

Duplicate issue, already fixed