Here is the video I used to add a bad ass level attribute. Anything can be an attribute, gender, birthday, shoe size etc. Maybe add something practical :3

https://www.youtube.com/watch?v=RaqIeNnxVU0

This, unfortunately, is not something that can be searched for, I might play around with it and try to make it a little bit more obvious. You can also make classes the same way with a few changes! 

Here's the script. Copy and paste it into a text file, save it and rename it to OID script.vbs the icon will change and generate a root OID code for your attribute. It's really weird :D

https://gallery.technet.microsoft.com/scriptcenter/56b78004-40d0-41cf-b95e-6e795b2e8a06