This spawned on my console. Maybe zLib related.
org.bukkit.event.EventException
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:502) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:487) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at org.bukkit.craftbukkit.v1_9_R1.event.CraftEventFactory.callPlayerInteractEvent(CraftEventFactory.java:231) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.PlayerInteractManager.a(PlayerInteractManager.java:482) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.PlayerConnection.a(PlayerConnection.java:888) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.PacketPlayInUseItem.a(SourceFile:55) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.PacketPlayInUseItem.a(SourceFile:11) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_91]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_91]
at net.minecraft.server.v1_9_R1.SystemUtils.a(SourceFile:45) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.MinecraftServer.D(MinecraftServer.java:721) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.DedicatedServer.D(DedicatedServer.java:400) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.MinecraftServer.C(MinecraftServer.java:660) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at net.minecraft.server.v1_9_R1.MinecraftServer.run(MinecraftServer.java:559) [spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_91]
Caused by: java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.Long
at eu.carrade.amaury.BelovedBlocks.zlib.components.attributes.Attributes.indexOf(Attributes.java:277) ~[?:?]
at eu.carrade.amaury.BelovedBlocks.zlib.components.attributes.Attributes.find(Attributes.java:314) ~[?:?]
at eu.carrade.amaury.BelovedBlocks.zlib.components.attributes.Attributes.get(Attributes.java:465) ~[?:?]
at eu.carrade.amaury.BelovedBlocks.BelovedItem$Attribute.fromItem(BelovedItem.java:63) ~[?:?]
at eu.carrade.amaury.BelovedBlocks.BelovedItemsManager.getFromItem(BelovedItemsManager.java:106) ~[?:?]
at eu.carrade.amaury.BelovedBlocks.tools.ToolsManager.use(ToolsManager.java:63) ~[?:?]
at eu.carrade.amaury.BelovedBlocks.listeners.BlocksListener.onPlayerInteract(BlocksListener.java:61) ~[?:?]
at sun.reflect.GeneratedMethodAccessor96.invoke(Unknown Source) ~[?:?]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_91]
at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_91]
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-1.9.2.jar:git-Spigot-e000104-4cb3258]
... 17 more