Prior to today, all the mastery items in Brazil did not have stats and each one did something special for your character (1). Check your inventory and you will see that all the items were given stats as well. You can also see that my energy account is getting credit for having one of each item. Normally you just have the one that is highest in value. I'm sure this will be fixed at some point but many players are enjoying a boost in their attack and defense scores.
(click image to enlarge)