It's a free idle game. There's not much to do to begin with and there's nothing to do after first 2 weeks. Seriously needs an event where you battle on new event maps or something similar. To me, a store discount is not a game event, that's called a sale. Bingo battle is also garbage, you battle with other people's best setup, but you can only use your characters once. After you've fought enough to complete one bingo, all that's left are your weak characters. How do you expect to best the rest?