General Information

Describe the bug:
Upon donning copper armor pieces, or holding in player hand, client is kicked from server.

To Reproduce:
Attempt to utilize copper armor while on a server running Forge 1.12.2 version 2854 (and 2847).
Does not occur in single player.

Mystic Mods Versions
mysticalworld-1.12.2-1.9.1.jar
mysticallib-1.12.2-1.9.0.jar
Patchouli-1.0-21.jar

Other Versions:

• Forge: 1.12.2 - 14.23.5.2854
• Minecraft: 1.12.2

Latest Server Log:
(Log copied after player kick)

[15:33:00] [Server thread/WARN] [net.minecraft.network.NetworkSystem]: Failed to handle packet for /127.0.0.1:53999
net.minecraft.util.ReportedException: Ticking player
at net.minecraft.entity.player.EntityPlayerMP.func_71127_g(EntityPlayerMP.java:459) ~[oq.class:?]
at net.minecraft.network.NetHandlerPlayServer.func_73660_a(NetHandlerPlayServer.java:173) ~[pa.class:?]
at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher$1.func_73660_a(NetworkDispatcher.java:209) ~[NetworkDispatcher$1.class:?]
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:285) ~[gw.class:?]
at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:180) [oz.class:?]
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:790) [MinecraftServer.class:?]
at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:397) [nz.class:?]
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:668) [MinecraftServer.class:?]
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526) [MinecraftServer.class:?]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_261]
Caused by: java.lang.NoSuchMethodError: epicsquid.mysticalworld.item.ItemCopperArmor.func_185083_B_()Lnet/minecraft/inventory/EntityEquipmentSlot;
at epicsquid.mysticalworld.item.ItemCopperArmor.getAttributeModifiers(ItemCopperArmor.java:26) ~[ItemCopperArmor.class:?]
at net.minecraft.item.ItemStack.func_111283_C(ItemStack.java:1016) ~[aip.class:?]
at net.minecraft.entity.EntityLivingBase.func_70071_h_(EntityLivingBase.java:2149) ~[vp.class:?]
at net.minecraft.entity.player.EntityPlayer.func_70071_h_(EntityPlayer.java:234) ~[aed.class:?]
at net.minecraft.entity.player.EntityPlayerMP.func_71127_g(EntityPlayerMP.java:382) ~[oq.class:?]
... 9 more

I believe this should be fixed in the most recent release.

Dang that was quick! I'll test it within the next few hours and report back.

That seems to have solved it. Updated to 1.9.2 on client and server. Modpack release has been updated for users.

Thank you so much.

This is my first time submitting something to GitHub. Apologies for the multiple posts. Was trying to edit previous ones and somehow derped, submitting the edits as new issues.

So to my humiliation the "getEquipmentSlot" function is client-side-only in 1.12 which is something I didn't check for. I'll release an update shortly.