The player level limit is 50.When your player level reaches 50, you can perform an action called"Prestige".
Performing Prestige resets your items, minion party slots, etc. and sends your player level back to 1. This may seem counter-productive, but doing so will allow you to obtain special items.

*If a guest player uses an profile with a Prestige Rank higher than 13, the guest profile will have its Prestige Rank reduced to 13.