I got to Level 16 yesterday and Level 17 today. I don't know how it happen. 2 days ago I was Level 15.92% then yesterday I got to Level 16.52% and today I'm Level 17.6% and I found out what each Level means in this the Welcome Newbies Forum. So this is what it means:

Level 16 - Magician Lord - A ****c SNK action-adventure game placing you in the role of a magician lord seeking out eight books of wisdom while fighting off enemies with numerous types of magic.

Level 17 - Minus World - A hidden level from Super Mario Bros. for the NES.