monster appoc hit mob

[SEVERE] Could not pass event EntityDamageByEntityEvent to Monster_Apocalypse v<16.1>
 org.bukkit.event.EventException
  at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:294) ~[Spigot.jar:git-Spigot-1385]
  at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[Spigot.jar:git-Spigot-1385]
  at org.bukkit.plugin.TimedRegisteredListener.callEvent(TimedRegisteredListener.java:47) ~[Spigot.jar:git-Spigot-1385]
  at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [Spigot.jar:git-Spigot-1385]
  at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [Spigot.jar:git-Spigot-1385]
  at org.bukkit.craftbukkit.v1_7_R2.event.CraftEventFactory.callEvent(CraftEventFactory.java:99) [Spigot.jar:git-Spigot-1385]
  at org.bukkit.craftbukkit.v1_7_R2.event.CraftEventFactory.callEntityDamageEvent(CraftEventFactory.java:403) [Spigot.jar:git-Spigot-1385]
  at org.bukkit.craftbukkit.v1_7_R2.event.CraftEventFactory.handleEntityDamageEvent(CraftEventFactory.java:430) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.EntityLiving.damageEntity(EntityLiving.java:663) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.EntityAnimal.damageEntity(SourceFile:145) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.EntityHuman.attack(EntityHuman.java:923) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.PlayerConnection.a(PlayerConnection.java:1144) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.PacketPlayInUseEntity.a(SourceFile:55) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.PacketPlayInUseEntity.handle(SourceFile:10) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.NetworkManager.a(NetworkManager.java:148) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.ServerConnection.c(ServerConnection.java:77) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.MinecraftServer.v(MinecraftServer.java:705) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.DedicatedServer.v(DedicatedServer.java:273) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.MinecraftServer.u(MinecraftServer.java:568) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.MinecraftServer.run(MinecraftServer.java:474) [Spigot.jar:git-Spigot-1385]
  at net.minecraft.server.v1_7_R2.ThreadServerApplication.run(SourceFile:618) [Spigot.jar:git-Spigot-1385]
 Caused by: java.lang.NoClassDefFoundError: org/bukkit/craftbukkit/v1_7_R3/entity/CraftArrow
  at blainicus.MonsterApocalypse.DamageListener.onEntityDamage(DamageListener.java:83) ~[?:?]
  at sun.reflect.GeneratedMethodAccessor199.invoke(Unknown Source) ~[?:?]
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.7.0_45]
  at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.7.0_45]
10:50:32 PM  at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:292) ~[Spigot.jar:git-Spigot-1385]
10:50:32 PM  ... 20 more
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