[19:36:46] [Server thread/ERROR]: Could not pass event PlayerChangedWorldEvent to MultiInv v3.3.5
org.bukkit.event.EventException
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot.jar:git-Spigot-44c59bf-1880a9c]
    at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot.jar:git-Spigot-44c59bf-1880a9c]
    at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at net.minecraft.server.v1_8_R3.PlayerList.moveToWorld(PlayerList.java:623) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at org.bukkit.craftbukkit.v1_8_R3.entity.CraftPlayer.teleport(CraftPlayer.java:476) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    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_8_R3.scheduler.CraftTask.run(CraftTask.java:71) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:350) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:726) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:367) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:657) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:560) [spigot.jar:git-Spigot-44c59bf-1880a9c]
    at java.lang.Thread.run(Thread.java:745) [?:1.8.0_45]
Caused by: java.lang.NullPointerException
    at uk.co.tggl.pluckerpluck.multiinv.inventory.MIItemStack.getItemMetaSerialized(MIItemStack.java:540) ~[?:?]
    at uk.co.tggl.pluckerpluck.multiinv.inventory.MIItemStack.<init>(MIItemStack.java:72) ~[?:?]
    at uk.co.tggl.pluckerpluck.multiinv.inventory.MIInventory.<init>(MIInventory.java:31) ~[?:?]
    at uk.co.tggl.pluckerpluck.multiinv.player.MIPlayer.saveAll(MIPlayer.java:104) ~[?:?]
    at uk.co.tggl.pluckerpluck.multiinv.listener.MIPlayerListener.savePlayerState(MIPlayerListener.java:506) ~[?:?]
    at uk.co.tggl.pluckerpluck.multiinv.listener.MIPlayerListener.onPlayerChangedWorld(MIPlayerListener.java:356) ~[?:?]
    at sun.reflect.GeneratedMethodAccessor755.invoke(Unknown Source) ~[?:?]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_45]
    at java.lang.reflect.Method.invoke(Method.java:497) ~[?:1.8.0_45]
    at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot.jar:git-Spigot-44c59bf-1880a9c]
    ... 14 more