XP Storage

Tested on Minecraft 1.14.4
(probably work on older versions too, if you test it, please comment so I can update the description :) )

Features

• Store whole XP levels in signs
• Retrieve XP levels from owned XP signs
• Only the owner of a sign is able to break it (As long as there are XP levels stored on it)
• Only the owner of the XP levels can retrieve and increase the XP levels

Usage
Create a new XP sign

1. Make an empty birch sign
2. Right click the sign with an emerald in your hand to store your levels to it and claim it

Update an existing XP sign

1. Right click your own exisiting XP sign with an emerald in your hand to update the XP stored on the sign

Retrieve XP from sign

1. Left click the sign with an emerald in your hand to retrieve your levels