i'm sure they will say it's a percentage of a percentage like with evony you can and i have failed at 100% success rate. 12 seems a lil excessive on 1 hero, it will be a while before I can give it a 13th shot. I'm rank 1 in arena which for me I never get gems as stakes and if anyone around me does they are guild members. Dumping that many medals to get nowhere is pretty painful but i'm failing multiple cards at 90% success rate also so i guess they are just having their way with my account. Upset about my posts or notes to customer support : )