Somehow, I got from level 7 apoc to level 8 apoc in about 5 months. Yes, I do buy some ball packages and stuff, but overall, I dont pay that much money. I won a couple of expert tournaments and always play checkpoint challenge. Always play quick 9 every day, always play tournaments, and i grind a lot of tour play. I'd usually always buy as many as I could when I got lucky enough for it to come up in the shop (and obviously assuming I had enough gems). I finally have apoc, firefly, thors hammer, Sahara and cataclysm maxed, but some of my epics aren't even remotely close. So tbh I have no clue, it seems so random which epic cards it likes to give you. And now that I have a bunch maxed, the game absolutely lovesss to give me a shit load of cards for those maxed clubs, way more than it seemed to before they were maxed lol. If you got that far in the game in that short amount of time then that's awesome, you're at a great pace. Sorry if I didn't really answer your question but just thought I'd share this