Farming Baze...

Sion was available only in packs and finally in the crystal store. I have him 7 star completely ftp and he's probably one of the hardest to get. But he worked with my arena team so it was worth it. The players that think Baze is worth it will get him to 7 star one way or another. With refreshes it can probably be done quickly enough if you're willing to spend the crystals. Personally for Baze and many hard nodes I'm not willing to spend crystals to refresh. I just farm two or three hard nodes at a time.