[21:47:37 ERROR]: Could not pass event EntityDeathEvent to BossLand v0.5
java.lang.IllegalArgumentException: Item cannot be null
        at org.apache.commons.lang.Validate.noNullElements(Validate.java:364) ~[patched_1.16.1.jar:git-Paper-111]
        at org.bukkit.craftbukkit.v1_16_R1.inventory.CraftInventory.addItem(CraftInventory.java:287) ~[patched_1.16.1.jar:git-Paper-111]
        at io.hotmail.com.jacob_vejvoda.BossLand.BossLand.onEntityDeath(BossLand.java:1945) ~[?:?]
        at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor287.execute(Unknown Source) ~[?:?]        at org.bukkit.plugin.EventExecutor.lambda$create$1(EventExecutor.java:69) ~[patched_1.16.1.jar:git-Paper-111]
        at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[patched_1.16.1.jar:git-Paper-111]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[patched_1.16.1.jar:git-Paper-111]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:607) ~[patched_1.16.1.jar:git-Paper-111]
        at org.bukkit.craftbukkit.v1_16_R1.event.CraftEventFactory.callEntityDeathEvent(CraftEventFactory.java:794) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.EntityLiving.d(EntityLiving.java:1489) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.EntityLiving.die(EntityLiving.java:1417) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.EntityLiving.damageEntity(EntityLiving.java:1261) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.EntityMonster.damageEntity(EntityMonster.java:52) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.EntityHuman.attack(EntityHuman.java:1092) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.EntityPlayer.attack(EntityPlayer.java:1861) ~[patched_1.16.1.jar:git-Paper-111]        at net.minecraft.server.v1_16_R1.PlayerConnection.a(PlayerConnection.java:2139) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.PacketPlayInUseEntity.a(PacketPlayInUseEntity.java:49) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.PacketPlayInUseEntity.a(PacketPlayInUseEntity.java:6) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.PlayerConnectionUtils.lambda$ensureMainThread$1(PlayerConnectionUtils.java:23) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.TickTask.run(SourceFile:18) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.executeTask(IAsyncTaskHandler.java:136) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.executeNext(IAsyncTaskHandler.java:109) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.MinecraftServer.aZ(MinecraftServer.java:1136) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.MinecraftServer.executeNext(MinecraftServer.java:1129) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.awaitTasks(IAsyncTaskHandler.java:119) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.MinecraftServer.sleepForTick(MinecraftServer.java:1090) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.MinecraftServer.v(MinecraftServer.java:1004) ~[patched_1.16.1.jar:git-Paper-111]
        at net.minecraft.server.v1_16_R1.MinecraftServer.lambda$a$0(MinecraftServer.java:177) ~[patched_1.16.1.jar:git-Paper-111]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_251]
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