java.lang.NullPointerException: Ticking entity
	at net.minecraft.entity.EntityLivingBase.func_70690_d(EntityLivingBase.java:741)
	at nightkosh.gravestone_extended.entity.monster.crawler.EntitySkullCrawler.func_70652_k(EntitySkullCrawler.java:266)
	at net.minecraft.entity.ai.EntityAIAttackMelee.func_190102_a(EntityAIAttackMelee.java:178)
	at net.minecraft.entity.ai.EntityAIAttackMelee.func_75246_d(EntityAIAttackMelee.java:167)
	at net.minecraft.entity.ai.EntityAITasks.func_75774_a(SourceFile:129)
	at net.minecraft.entity.EntityLiving.func_70626_be(EntityLiving.java:894)
	at net.minecraft.entity.EntityLivingBase.func_70636_d(EntityLivingBase.java:2347)
	at net.minecraft.entity.EntityLiving.func_70636_d(EntityLiving.java:689)
	at net.minecraft.entity.monster.EntityMob.func_70636_d(EntityMob.java:45)
	at nightkosh.gravestone_extended.entity.monster.crawler.EntitySkullCrawler.func_70636_d(EntitySkullCrawler.java:294)
	at net.minecraft.entity.EntityLivingBase.func_70071_h_(EntityLivingBase.java:2167)
	at net.minecraft.entity.EntityLiving.func_70071_h_(EntityLiving.java:388)
	at net.minecraft.entity.monster.EntityMob.func_70071_h_(EntityMob.java:50)
	at nightkosh.gravestone_extended.entity.monster.crawler.EntitySkullCrawler.func_70071_h_(EntitySkullCrawler.java:128)
	at net.minecraft.world.World.func_72866_a(World.java:1986)
	at net.minecraft.world.WorldServer.func_72866_a(WorldServer.java:831)
	at net.minecraft.world.World.func_72870_g(World.java:1948)
	at net.minecraft.world.World.func_72939_s(World.java:1755)
	at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:612)
	at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:765)
	at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:666)
	at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:239)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:524)
	at java.lang.Thread.run(Thread.java:745)