Crash

---- Minecraft Crash Report ----

WARNING: coremods are present:
  SpongeCoremod (spongeforge-1.10.2-2281-5.2.0-BETA-2422.jar)
Contact their authors BEFORE contacting forge

// You're mean.

Time: 7/4/17 11:06 AM
Description: Exception in server tick loop

java.lang.IllegalArgumentException: Don't know how to add class com.pixelmonmod.pixelmon.entities.npcs.NPCRelearner!
	at net.minecraft.entity.EntityTrackerEntry.func_151260_c(EntityTrackerEntry.java:632)
	at net.minecraft.entity.EntityTrackerEntry.func_73117_b(EntityTrackerEntry.java:371)
	at net.minecraft.entity.EntityTracker.func_72788_a(EntityTracker.java:303)
	at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:721)
	at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:387)
	at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:613)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:471)
	at java.lang.Thread.run(Thread.java:748)


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

-- Head --
Thread: Server thread
Stacktrace:
	at net.minecraft.entity.EntityTrackerEntry.func_151260_c(EntityTrackerEntry.java:632)
	at net.minecraft.entity.EntityTrackerEntry.func_73117_b(EntityTrackerEntry.java:371)
	at net.minecraft.entity.EntityTracker.func_72788_a(EntityTracker.java:303)

-- Sponge CauseTracker --
Details:
	Cause Stack: [Empty stack]
Stacktrace:
	at net.minecraft.server.MinecraftServer.handler$onCrashReport$zho000(MinecraftServer.java:3937)
	at net.minecraft.server.MinecraftServer.func_71230_b(MinecraftServer.java:829)
	at net.minecraft.server.dedicated.DedicatedServer.func_71230_b(DedicatedServer.java:361)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:503)
	at java.lang.Thread.run(Thread.java:748)