I used to love this game, but since they switched to a season pass system they've done nothing, zero, zip to address the issue of people who'd already bought all the pre-season pass songs not being able to use the reward cards from the pass for anything. I even skipped the last season pass to see if those songs would join the unlockable by cards pool, but they did not. There's even a bunch of songs I could buy with gems but for whatever reason can't be unlocked with season reward cards.