I am ADDICTED to this game! It's really fun when you start playing, but when you get to the high levels and compete against tougher opponents, the game loses its meaning. It is skill based, however, it still doesn't work. I am player level 9 and have level 9 characters, but I get put with level 12 players/characters. Characters cost more rings to upgrade as they level up, to the point where you either have to grind on the game for hours to get enough rings or spend a load of money on rings.