Describe the Bug:
Is a bug with the mod: When Dungeons Arise (https://www.curseforge.com/minecraft/mc-mods/when-dungeons-arise) in one of them structures
Is an spawner. Skeleton spawner on that ship
That has a magma slime riding it

How to Reproduce:
Well, in Discord,
Kaleidio (Modpack dev) told me:

• might wanna bug report this to infernal expansion team. it looks like their custom slimes do something bad with spawn/pathfinding code.
• I assumed the slime is somewhere they aren't able to see
  either that or the mixin is so broken it crossed over into slime ai bytecode somehow
  ah yea magma slime
  infernal expansion is a nether mod so that's definitely what gone wrong here. their magma slime override

Expected Behavior:
It just happen when I come close, and the spawners are activated, I mean, just happened with the entities

Screenshots:
The ISSUE START HERE at [10:12:06]
[10:01:59] [SoundControl Sound Processor/WARN] [SoundControl/SoundFXProcessor]: SoundControl Sound Processor is lagging; behind 16 msecs
[10:02:54] [Render thread/INFO] [minecraft/NewChatGui]: [CHAT] Respawn point set
[10:03:46] [Render thread/INFO] [minecraft/AdvancementList]: Loaded 414 advancements
[10:06:58] [Server thread/INFO] [co.si.sh.ut.cu.Utils/]: Saving config options on path: C:\Users\JUANCARLOS\AppData\Roaming.minecraft\shrines-saves
[10:06:58] [Server thread/INFO] [co.si.sh.ut.cu.Utils/]: Saving config options on path: C:\Users\JUANCARLOS\AppData\Roaming.minecraft\shrines-saves
[10:06:58] [Server thread/INFO] [co.si.sh.ut.cu.Utils/]: Saving config options on path: C:\Users\JUANCARLOS\AppData\Roaming.minecraft\shrines-saves
[10:06:58] [Server thread/INFO] [co.si.sh.ut.cu.Utils/]: Saving config options on path: C:\Users\JUANCARLOS\AppData\Roaming.minecraft\shrines-saves
[10:07:27] [Server thread/WARN] [minecraft/LootTable]: Tried to over-fill a container
[10:08:01] [Render thread/INFO] [minecraft/AdvancementList]: Loaded 417 advancements
[10:11:47] [Render thread/INFO] [minecraft/AdvancementList]: Loaded 417 advancements
[10:11:58] [Server thread/INFO] [co.si.sh.ut.cu.Utils/]: Saving config options on path: C:\Users\JUANCARLOS\AppData\Roaming.minecraft\shrines-saves
[10:11:58] [Server thread/INFO] [co.si.sh.ut.cu.Utils/]: Saving config options on path: C:\Users\JUANCARLOS\AppData\Roaming.minecraft\shrines-saves
[10:11:58] [Server thread/INFO] [co.si.sh.ut.cu.Utils/]: Saving config options on path: C:\Users\JUANCARLOS\AppData\Roaming.minecraft\shrines-saves
[10:11:58] [Server thread/INFO] [co.si.sh.ut.cu.Utils/]: Saving config options on path: C:\Users\JUANCARLOS\AppData\Roaming.minecraft\shrines-saves
[10:12:06] [Server thread/ERROR] [ne.mi.ev.EventBus/EVENTBUS]: Exception caught during firing event: net.minecraft.entity.ai.controller.MovementController cannot be cast to net.minecraft.entity.monster.SlimeEntity$MoveHelperController
Index: 9
Listeners:
0: HIGHEST
1: ASM: net.minecraftforge.common.ForgeInternalHandler@9c63984 onEntityJoinWorld(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
2: ASM: class org.orecruncher.lib.effects.EntityEffectHandler onEntityJoin(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
3: NORMAL
4: ASM: class com.maciej916.maenchants.common.subscribers.ForgeEventSubscriber onEntityJoinWorld(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
5: ASM: net.mcreator.comfortablenether.procedures.PiglinBruteAxeProcedure@7aa80202 onEntitySpawned(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
6: ASM: class me.marnic.extrabows.common.events.ExtraBowsEventHandler arrowConstructing(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
7: ASM: com.github.alexthe666.citadel.server.CitadelEvents@40685f0 onJoinWorld(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
8: ASM: com.nekomaster1000.infernalexp.events.MiscEvents@7dc680e8 onEntityJoin(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
9: ASM: com.nekomaster1000.infernalexp.events.MobEvents@1fa8278e onEntityJoin(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
10: net.minecraftforge.eventbus.EventBus$$Lambda$2969/556272827@48ad8970
11: ASM: class org.orecruncher.lib.service.ModuleServiceManager entityJoinWorld(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
12: ASM: INSTANCE onEntityJoinWorld(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
13: ASM: com.blackgear.cavesandcliffs.common.events.EntityGoalEvents@49bd2e8b onEntityJoin(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
14: ASM: class com.legacy.dungeons_plus.DPEvents onEntitySpawn(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
15: ASM: class com.minecraftabnormals.savageandravage.core.other.SREvents onLivingSpawned(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
16: ASM: class baguchan.hunterillager.event.EntityEvent addSpawn(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
17: ASM: com.baranhan.undefeatables.handlers.MobCreationHandler@2778d068 onSpawn(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
18: ASM: top.theillusivec4.champions.common.ChampionEventsHandler@793f08d6 onLivingJoinWorld(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
19: ASM: top.theillusivec4.curios.common.event.CuriosEventHandler@669fdf1d entityJoinWorld(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
20: LOWEST
21: ASM: class com.minecraftabnormals.upgrade_aquatic.core.events.EntityEvents onEntitySpawned(Lnet/minecraftforge/event/entity/EntityJoinWorldEvent;)V
java.lang.ClassCastException: net.minecraft.entity.ai.controller.MovementController cannot be cast to net.minecraft.entity.monster.SlimeEntity$MoveHelperController
at com.nekomaster1000.infernalexp.entities.ai.AvoidBlockGoal.(AvoidBlockGoal.java:34)
at com.nekomaster1000.infernalexp.entities.ai.AvoidBlockGoal.(AvoidBlockGoal.java:25)
at com.nekomaster1000.infernalexp.events.MobEvents.onEntityJoin(MobEvents.java:169)
at net.minecraftforge.eventbus.ASMEventHandler_289_MobEvents_onEntityJoin_EntityJoinWorldEvent.invoke(.dynamic)
at net.minecraftforge.eventbus.ASMEventHandler.invoke(ASMEventHandler.java:85)
at net.minecraftforge.eventbus.EventBus$$Lambda$2579/1281045190.invoke(Unknown Source)
at net.minecraftforge.eventbus.EventBus.post(EventBus.java:302)
at net.minecraftforge.eventbus.EventBus.post(EventBus.java:283)
at net.minecraft.world.server.ServerWorld.func_72838_d(ServerWorld.java:813)
at net.minecraft.world.server.ServerWorld.func_217376_c(ServerWorld.java:754)
at net.minecraft.world.IServerWorld$$Lambda$14555/222070795.accept(Unknown Source)
at java.util.stream.StreamSpliterators$WrappingSpliterator$$Lambda$2147/1415108264.accept(Unknown Source)
at java.util.stream.Streams$StreamBuilderImpl.forEachRemaining(Streams.java:419)
at java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:742)
at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:580)
at java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:270)
at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1374)
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:512)
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:502)
at java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:312)
at java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:743)
at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:580)
at net.minecraft.world.IServerWorld.func_242417_l(SourceFile:11)
at net.minecraft.world.server.ServerWorld.func_242106_g(ServerWorld.java:868)
at net.minecraft.world.spawner.AbstractSpawner.func_98278_g(AbstractSpawner.java:144)
at net.minecraft.tileentity.MobSpawnerTileEntity.func_73660_a(SourceFile:62)
at net.minecraft.world.World.func_217391_K(World.java:491)
at net.minecraft.world.server.ServerWorld.func_72835_b(ServerWorld.java:371)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:851)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:787)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:118)
at net.minecraft.server.MinecraftServer.func_240802_v_(MinecraftServer.java:642)
at net.minecraft.server.MinecraftServer.func_240783_a_(MinecraftServer.java:232)
at net.minecraft.server.MinecraftServer$$Lambda$12813/1291209693.run(Unknown Source)
at java.lang.Thread.run(Thread.java:745)

[10:12:07] [Server thread/FATAL] [ne.mi.co.ForgeMod/]: Preparing crash report with UUID 2b7cd318-6154-4e6d-be5d-c48bee092632
[10:12:07] [Server thread/ERROR] [minecraft/MinecraftServer]: Encountered an unexpected exception
net.minecraft.crash.ReportedException: Ticking block entity
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:855) ~[?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:APP:enhancedcelestials.mixins.json:MixinMinecraftServer,pl:mixin:A}
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:787) ~[?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:APP:enhancedcelestials.mixins.json:MixinMinecraftServer,pl:mixin:A}
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:118) ~[?:?] {re:classloading,xf:OptiFine:default}
at net.minecraft.server.MinecraftServer.func_240802_v_(MinecraftServer.java:642) [?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:APP:enhancedcelestials.mixins.json:MixinMinecraftServer,pl:mixin:A}
at net.minecraft.server.MinecraftServer.func_240783_a_(MinecraftServer.java:232) [?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:APP:enhancedcelestials.mixins.json:MixinMinecraftServer,pl:mixin:A}
at net.minecraft.server.MinecraftServer$$Lambda$12813/1291209693.run(Unknown Source) [?:?] {}
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_51] {}
Caused by: java.lang.ClassCastException: net.minecraft.entity.ai.controller.MovementController cannot be cast to net.minecraft.entity.monster.SlimeEntity$MoveHelperController
at com.nekomaster1000.infernalexp.entities.ai.AvoidBlockGoal.(AvoidBlockGoal.java:34) ~[?:2.0.0-beta.5] {re:classloading}
at com.nekomaster1000.infernalexp.entities.ai.AvoidBlockGoal.(AvoidBlockGoal.java:25) ~[?:2.0.0-beta.5] {re:classloading}
at com.nekomaster1000.infernalexp.events.MobEvents.onEntityJoin(MobEvents.java:169) ~[?:2.0.0-beta.5] {re:classloading}
at net.minecraftforge.eventbus.ASMEventHandler_289_MobEvents_onEntityJoin_EntityJoinWorldEvent.invoke(.dynamic) ~[?:?] {}
at net.minecraftforge.eventbus.ASMEventHandler.invoke(ASMEventHandler.java:85) ~[eventbus-4.0.0.jar:?] {}
at net.minecraftforge.eventbus.EventBus$$Lambda$2579/1281045190.invoke(Unknown Source) ~[?:?] {}
at net.minecraftforge.eventbus.EventBus.post(EventBus.java:302) ~[eventbus-4.0.0.jar:?] {}
at net.minecraftforge.eventbus.EventBus.post(EventBus.java:283) ~[eventbus-4.0.0.jar:?] {}
at net.minecraft.world.server.ServerWorld.func_72838_d(ServerWorld.java:813) ~[?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,xf:fml:forgeendertech:coremod,pl:mixin:APP:abnormals_core.mixins.json:ServerWorldMixin,pl:mixin:APP:endergetic.mixins.json:ServerWorldMixin,pl:mixin:APP:cavesandcliffs.mixins.json:common.world.gen.ServerWorldMixin,pl:mixin:A}
at net.minecraft.world.server.ServerWorld.func_217376_c(ServerWorld.java:754) ~[?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,xf:fml:forgeendertech:coremod,pl:mixin:APP:abnormals_core.mixins.json:ServerWorldMixin,pl:mixin:APP:endergetic.mixins.json:ServerWorldMixin,pl:mixin:APP:cavesandcliffs.mixins.json:common.world.gen.ServerWorldMixin,pl:mixin:A}
at net.minecraft.world.IServerWorld$$Lambda$14555/222070795.accept(Unknown Source) ~[?:?] {}
at java.util.stream.StreamSpliterators$WrappingSpliterator$$Lambda$2147/1415108264.accept(Unknown Source) ~[?:?] {}
at java.util.stream.Streams$StreamBuilderImpl.forEachRemaining(Streams.java:419) ~[?:1.8.0_51] {}
at java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:742) ~[?:1.8.0_51] {}
at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:580) ~[?:1.8.0_51] {}
at java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:270) ~[?:1.8.0_51] {}
at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1374) ~[?:1.8.0_51] {}
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:512) ~[?:1.8.0_51] {}
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:502) ~[?:1.8.0_51] {}
at java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:312) ~[?:1.8.0_51] {}
at java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:743) ~[?:1.8.0_51] {}
at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:580) ~[?:1.8.0_51] {}
at net.minecraft.world.IServerWorld.func_242417_l(SourceFile:11) ~[?:?] {re:computing_frames,re:mixin,re:classloading}
at net.minecraft.world.server.ServerWorld.func_242106_g(ServerWorld.java:868) ~[?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,xf:fml:forgeendertech:coremod,pl:mixin:APP:abnormals_core.mixins.json:ServerWorldMixin,pl:mixin:APP:endergetic.mixins.json:ServerWorldMixin,pl:mixin:APP:cavesandcliffs.mixins.json:common.world.gen.ServerWorldMixin,pl:mixin:A}
at net.minecraft.world.spawner.AbstractSpawner.func_98278_g(AbstractSpawner.java:144) ~[?:?] {re:classloading}
at net.minecraft.tileentity.MobSpawnerTileEntity.func_73660_a(SourceFile:62) ~[?:?] {re:classloading}
at net.minecraft.world.World.func_217391_K(World.java:491) ~[?:?] {re:computing_frames,pl:accesstransformer:B,re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B}
at net.minecraft.world.server.ServerWorld.func_72835_b(ServerWorld.java:371) ~[?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,xf:fml:forgeendertech:coremod,pl:mixin:APP:abnormals_core.mixins.json:ServerWorldMixin,pl:mixin:APP:endergetic.mixins.json:ServerWorldMixin,pl:mixin:APP:cavesandcliffs.mixins.json:common.world.gen.ServerWorldMixin,pl:mixin:A}
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:851) ~[?:?] {re:mixin,pl:accesstransformer:B,re:classloading,pl:accesstransformer:B,pl:mixin:APP:structure_gel.mixins.json:MinecraftServerMixin,pl:mixin:APP:enhancedcelestials.mixins.json:MixinMinecraftServer,pl:mixin:A}
... 6 more
AL lib: (EE) alc_cleanup: 1 device not closed
Here I am!
[VersionManager] Refreshing versions locally...
[VersionManager] Versions has been refreshed (142 ms)
[Launcher] Minecraft closed with exit code: -1
[Launcher] Launcher exited.
flush now
flush now

Version Information:
Windows 10
(RAM) 8.00 GB
Intel(R) Core(TM) i5-1035G1 CPU @ 1.00GHz, 1190 Mhz
Mod List:
TreeChop-1.16.4-0.14.4.jar
Ma-Enchants-1.16.5-3.6.0.jar
infernal-expansion-2.0.0-beta.5.jar
Shrines-1.16.5-1.8.1.jar
PiratesAndLootersMotionUpdate.jar
jei-1.16.5-7.7.0.106.jar
ComfortableNether4.3.jar
abnormals_core-1.16.5-3.1.1.jar
looot-1.16.4-1.0.0.3.jar
Undefeatables+1.4.jar
toadterror-1.16.4-1.0.0.jar
BetterCaves-Forge-1.16.4-1.1.2.jar
Waystones_1.16.5-7.6.2.jar
ForgeEndertech-1.16.4-7.1.0.0-build.0075.jar
AdFinders-1.16.4-5.0.8.0-build.0115.jar
citadel-1.7.0-1.16.5.jar
alexsmobs-1.11.1.jar
YungsApi-1.16.4-Forge-11.jar
environmental-1.16.5-1.0.0.jar
champions-forge-1.16.5-2.0.1.7.jar
DungeonCrawl-1.16.3-2.2.4.jar
toolleveling-1.16.5-1.2.4.jar
u_team_core-1.16.5-3.2.0.194.jar
outvoted-1.16.5-1.2.4.jar
forge-1.16.5-36.1.0-universal.jar
NoIncreasingRepairCost-1.16.4-1.0.0.jar
meetyourfight-1.16.5-1.1.2.jar
DynamicSurroundings-1.16.4-4.0.4.2.jar
structure_gel-1.16.5-1.7.7.jar
DungeonsArise-1.16.5-2.1.45-release.jar
forge-1.16.5-36.1.0-client.jar
cavebiomes-2.0.jar
upgrade_aquatic-1.16.5-3.1.0.jar
cofh_core-1.16.4-1.2.1.jar
endergetic-1.16.4-3.0.0.jar
useful_backpacks-1.16.5-1.12.0.88.jar
repurposed_structures-1.16.5-2.7.10-forge.jar
compactores-1.16.5-3.0.3.jar
practicaltools-1.16.3-1.8.jar
dungeons_plus-1.16.5-1.1.5.jar
towers_of_the_wild-1.16.4-2.0.1.jar
CavesAndCliffsBackport-6.1.jar
DungeonsEnhanced-1.0.jar
atmospheric-1.16.5-3.1.0.jar
majrusz-library-1.16.4-2.0.1.jar
curios-forge-1.16.5-4.0.5.2.jar
Atum-1.16.5-2.2.5.jar
relics-0.2.3.1.jar
savageandravage-1.16.5-3.1.0.jar
Patchouli-1.16.4-51.jar
gravestone-1.16.5-1.0.5.jar
levelhearts-1.16.2-2.2.0.jar
StorageDrawers-1.16.3-8.2.2.jar
EndReborn+[0.8.4].jar
BetterStrongholds-1.16.4-1.2.jar
majruszs-difficulty-1.16.4-1.1.0.jar
workshopsofdoom-1.16.4-1.1.0.1.jar
HunterIllager-1.16.5-1.3.1.jar
enhancedcelestials-1.0.4-1.16.4.jar
FriendlyFire-1.16.5-7.0.2.jar
Disenchanting-forge-1.16.5-1.7.1.jar
BetterMineshafts-Forge-1.16.4-2.0.4.jar
geckolib-forge-1.16.5-3.0.41.jar
Additional Context:
At the end, when I remove Infernal Expansion mod, everything is fine after that

sorry, I didn't notice

Duplicate of #196. Already fixed in the latest version.