Rng and selective perception are a bad combination. Try to take a note of every miss and crit you and your opponent make in the different areas (eb, Arena, gw, friend battle) of the game. It will even out in the long run and its the only thing that adds a bit of luck to a rather dull "rock,paper,scissors" combat. Although i must admit that i almost smash my iPad from time to time because the misses infuriate me :d