Minecraft Forums

---- Minecraft Crash Report ----

WARNING: coremods are present:
Contact their authors BEFORE contacting forge

// You should try our sister game, Minceraft!

Time: xxxxxxxx (No shary)
Description: Exception in server tick loop

java.lang.NoClassDefFoundError: net/minecraft/entity/Entity$1
at net.minecraft.entity.Entity.func_85029_a(Entity.java:2481)
at net.minecraft.entity.Entity.func_70020_e(Entity.java:1715)
at net.minecraft.entity.EntityList.func_75615_a(EntityList.java:175)
at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_186053_a(AnvilChunkLoader.java:597)
at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_186050_a(AnvilChunkLoader.java:524)
at net.minecraft.world.chunk.storage.AnvilChunkLoader.loadEntities(AnvilChunkLoader.java:474)
at net.minecraftforge.common.chunkio.ChunkIOProvider.syncCallback(ChunkIOProvider.java:96)
at net.minecraftforge.common.chunkio.ChunkIOExecutor.tick(ChunkIOExecutor.java:150)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:673)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:613)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:149)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:471)
at java.lang.Thread.run(Unknown Source)

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

-- System Details --
Details:
Minecraft Version: 1.10.2
Operating System: Windows 8.1 (amd64) version 6.3
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 4175744816 bytes (3982 MB) / 5368709120 bytes (5120 MB) up to 5368709120 bytes (5120 MB)
JVM Flags: 5 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xms5120m -Xmx5120m -XX:+UseG1GC -XX:MaxGCPauseMillis=4
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
FML: MCP 9.32 Powered by Forge 12.18.1.2029 37 mods loaded, 37 mods active
States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored
UCHIJAAAA mcp{9.19} [Minecraft Coder Pack] (minecraft.jar)
UCHIJAAAA FML{8.0.99.99} [Forge Mod Loader] (modpack.jar)
UCHIJAAAA Forge{12.18.1.2029} [Minecraft Forge] (modpack.jar)
UCHIJAAAA adobeblocks{6.0.3.26} [Adobe Blocks 2] (AdobeBlocks-Forge-6.0.3.26-patched.jar)
UCHIJAAAA XaeroBetterPvP{1.9.9} [Better PVP Mod] (BetterPvP_1.9.9_Forge_1.10.2.jar)
UCHIJAAAA BetterSprinting{1.1.5} [Better Sprinting] (BetterSprinting MC-1.10 v1.1.5.jar)
UCHIJAAAA blockbuster{1.3.1-pre} [Blockbuster] (blockbuster-1.3.1-pre.jar)
UCHIJAAAA buttons{1.10.2-0.0.3-3} [Buttons] (Buttons-1.10.2-0.0.3-3.jar)
UCHIJAAAA calendarapi{1.5} [CalendarAPI] (Calendar-1.10.2-1.5-10.jar)
UCHIJAAAA cavern{1.1.0} [Cavern] (Cavern_1.10-v1.1.0.jar)
UCHIJAAAA ChestTransporter{2.5.0} [Chest Transporter] (ChestTransporter-1.10-2.5.0.jar)
UCHIJAAAA coroai{v1.1.9} [coroai] (coroutil-1.10.2-1.1.9.jar)
UCHIJAAAA extendedrenderer{v1.0} [Extended Renderer] (coroutil-1.10.2-1.1.9.jar)
UCHIJAAAA configmod{v1.0} [Extended Mod Config] (coroutil-1.10.2-1.1.9.jar)
UCHIJAAAA customspawner{3.10.0} [DrZhark's CustomSpawner] (CustomMobSpawner 3.10.0.jar)
UCHIJAAAA customnpcs{1.10.2} [CustomNPCs] (CustomNPCs_1.10.2(20nov16).jar)
UCHIJAAAA PTRModelLib{1.0.0} [PTRModelLib] (Decocraft-2.3.5_1.10.2.jar)
UCHIJAAAA props{2.3.4} [Decocraft] (Decocraft-2.3.5_1.10.2.jar)
UCHIJAAAA DragonMounts{r46-1.10.2} [Dragon Mounts] (DragonMounts-r46-1.10.2.jar)
UCHIJAAAA hammercore{1.1.2} [Hammer Core] (HammerCore_1.10.2-1.1.2.jar)
UCHIJAAAA IngameAccountSwitcher{6.1.1.72} [In-Game Account Switcher] (InGameAccountSwitcher-Forge-6.1.1.72.jar)
UCHIJAAAA InventoryPets{1.4.8.1} [Inventory Pets] (inventorypets-1.10-1.4.8.1.jar)
UCHIJAAAA ism{1.5.10 MC-1.10.2} [Instant Structures Mod (ISM)] (ism-1.5.10 MC-1.10.2.jar)
UCHIJAAAA jwin{univ_compat_filler} [Just What I Needed] (jwin-0.12.0_mc1.10.2.jar)
UCHIJAAAA krikkemod{1.0.3} [Krikke's Mod] (krikkemod-1.0.3.jar)
UCHIJAAAA obsidianglass{1.0.1} [Obsidian Glass] (obsidianglass-1.10-1.0.1 (1).jar)
UCHIJAAAA packingtape{0.5.2} [Packing Tape] (PackingTape-1.9.4-0.5.2.jar)
UCHIJAAAA possessed{1.0.0} [Possessed] (possessed-1.0.0.jar)
UCHIJAAAA RadixCore{1.10.2-2.1.3} [RadixCore] (RadixCore-1.10.2-2.1.3-universal.jar)
UCHIJAAAA rftl{1.0} [Rotten Flesh to Leather] (RFTL 1.0.jar)
UCHIJAAAA shadowmc{3.4.4} [ShadowMC] (ShadowMC-1.10.2-3.4.4.jar)
UCHIJAAAA showcasemod{0.2} [Showcase Mod] (showcasemod-0.3-1.10.2.jar)
UCHIJAAAA spawnercraft{3.1} [SpawnerCraft] (SpawnerCraft 1.10.2-3.2.0.jar)
UCHIJAAAA tails{1.10.2-1.8.3} [Tails] (Tails-1.10.2-1.8.3.jar)
UCHIJAAAA worldedit{6.1.4} [WorldEdit] (worldedit-forge-mc1.10.2-6.1.4-dist.jar)
UCHIJAAAA zombieawareness{v1.20} [Zombie Awareness] (zombieawareness-1.10.2-1.20.jar)
UCHIJAAAA mcmultipart{1.2.0} [MCMultiPart] (MCMultiPart-1.2.0-universal.jar)
Loaded coremods (and transformers):
Profiler Position: N/A (disabled)
Player Count: 1 / 8; [EntityPlayerMP['danigirl23'/1016, l='FNAF Universe', x=-178.90, y=67.62, z=-176.86]]
Type: Integrated Server (map_client.txt)
Is Modded: Definitely; Client brand changed to 'fml,forge'

That world is the only world to not work so far. The others do. Also I was on singleplayer

I got rid all the mods, and it works. It may be one of the mods, maybe trial and error