[21:11:03 ERROR]: Could not pass event PlayerChangedWorldEvent to MultiInv v3.3.6
org.bukkit.event.EventException
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at net.minecraft.server.v1_9_R2.PlayerList.moveToWorld(PlayerList.java:685) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at org.bukkit.craftbukkit.v1_9_R2.entity.CraftPlayer.teleport(CraftPlayer.java:471) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at com.earth2me.essentials.Teleport.now(Teleport.java:126) [Essentials.jar:?]
        at com.earth2me.essentials.TimedTeleport$1DelayedTeleportTask.run(TimedTeleport.java:131) [Essentials.jar:?]
        at org.bukkit.craftbukkit.v1_9_R2.scheduler.CraftTask.run(CraftTask.java:71) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at org.bukkit.craftbukkit.v1_9_R2.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:350) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at net.minecraft.server.v1_9_R2.MinecraftServer.D(MinecraftServer.java:734) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at net.minecraft.server.v1_9_R2.DedicatedServer.D(DedicatedServer.java:399) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at net.minecraft.server.v1_9_R2.MinecraftServer.C(MinecraftServer.java:665) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at net.minecraft.server.v1_9_R2.MinecraftServer.run(MinecraftServer.java:564) [spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_66]
Caused by: java.lang.NoClassDefFoundError: net/minecraft/server/v1_9_R1/NBTBase
        at uk.co.tggl.pluckerpluck.multiinv.inventory.MIItemStack.<init>(MIItemStack.java:64) ~[?:?]
        at uk.co.tggl.pluckerpluck.multiinv.inventory.MIInventory.<init>(MIInventory.java:34) ~[?:?]
        at uk.co.tggl.pluckerpluck.multiinv.player.MIPlayer.saveAll(MIPlayer.java:119) ~[?:?]
        at uk.co.tggl.pluckerpluck.multiinv.listener.MIPlayerListener.savePlayerState(MIPlayerListener.java:507) ~[?:?]
        at uk.co.tggl.pluckerpluck.multiinv.listener.MIPlayerListener.onPlayerChangedWorld(MIPlayerListener.java:356) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_66]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_66]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_66]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_66]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        ... 14 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_9_R1.NBTBase
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:91) ~[spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_66]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_66]
        at uk.co.tggl.pluckerpluck.multiinv.inventory.MIItemStack.<init>(MIItemStack.java:64) ~[?:?]
        at uk.co.tggl.pluckerpluck.multiinv.inventory.MIInventory.<init>(MIInventory.java:34) ~[?:?]
        at uk.co.tggl.pluckerpluck.multiinv.player.MIPlayer.saveAll(MIPlayer.java:119) ~[?:?]
        at uk.co.tggl.pluckerpluck.multiinv.listener.MIPlayerListener.savePlayerState(MIPlayerListener.java:507) ~[?:?]
        at uk.co.tggl.pluckerpluck.multiinv.listener.MIPlayerListener.onPlayerChangedWorld(MIPlayerListener.java:356) ~[?:?]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_66]
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_66]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_66]
        at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_66]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.9.4.jar:git-Spigot-4af49dc-4e19de1]