Qestion about nobility
You have to reach level 40 in Global. When you do, go to your Hub screen, and click the first box that highlights your money, RP, Global level, etc. Then, on the left side scroll down and highlight Nobility and click on it. Then on the next screen, move right, and select Level Up. It'll give you a brief message saying if you do, all tiers from the games will reset to level 1. Accept it, and you'll level up. So far, there's only 9 Nobility levels until DL decides to make more.
Don't worry - your gained RP will not reset to zero. Those are safe for you to purchase items or saving them up. Only the other games that you levelled up on will be reset back to level 1.