Version E, which is due out in a week or two, will be giving out player rewards. I don't know whether this will be experience for cards (probably), more cards (reasonable chance), something else (maybe) or some combination of those three (most likely). You could always join the Discord group (https://discord.gg/GZcYNXz) and ask Elindos. He is likely to give clues if not outright answers.

Welcome to EXODE!