We are planning to change the quest and season rewards to take the form of "loot chests" that will contain reward cards in addition to other things such as DEC and potions. The exact contents of the chests will be randomly determined, and the higher your league, the higher level chest you will receive with proportionally more rewards inside. It's important to note that we are not getting rid of the reward card system, and we still plan to introduce new reward cards from time to time (more on that below).
I absolutely hate this idea. Especially in a world where legislation are seriously considering putting laws against loot boxes. Just be upfront about it instead of having it be hidden and random.
You're in Gold II you get 10 cards and a potion and 500 DEC. There's already plenty of randomness within drawing cards without adding another layer of randomness to it.