Issue Description:

Rogue-adventures and Dungeons but I have added EnderIO to it.

What happens:

My game crashes anytime I try to open the XP Obelisk. Other EnderIO interfaces work fine. Happens both in a server and in single player.

What you expected to happen:

I expected the GUI to open and allow me to use the Obelisk.

Steps to reproduce:

1. Download Rogue-adventures and dungeons pack.
2. Add Ender core and EnderIO mods.
3. Get an XP Obelisk and try to right click it.
   ...

Affected Versions (Do not use "latest"):

• EnderIO:1.12.2-0.5.76
• EnderCore:1.12.2-5.2.62
• Minecraft:1.12.2
• Forge:14.23.5.2854
• SpongeForge? no
• Optifine? no
• Single Player and/or Server? Both in single player and on server (server does not crash only client side)

Your most recent log file where the issue was present:

[https://pastebin.com/HZ4F8XwA]

workaround: make sure you have at least one level when opening the obelisk

When trying this I had 9 levels.

Would it be possible to test with this build: https://ci.tterrag.com/job/EnderIO-Modules/job/EnderIO-Hourly/lastSuccessfulBuild/artifact/build/libs/EnderIO-1.12.2-5.2.1274-nightly.jar?

Thank you, that build works.

Thank you for the feedback. The fix will be part of the next release (which might be soon)