It might also be worth mentioning WIF in the answer as for what format that key needs to be in.

That sounds perfect! The second answer calls it Wallet Import Format or WIF and that's 100% what I was after! I guess that makes this question a duplicate. EDIT: they deleted their comment, but not after linking to this question.

I don't think a reward could be set up because you can't split the commodity in this scenario. If players set up pools and the reward for solving a block is a booster pack or a full deck then how could the pool possibly divide the cards up? Without pools then individuals with large mining rigs take over and have a monopoly which I think would spoil the game.

@m1xolyd1an Clients will still submit "transactions" (game stats, trades, etc) to be verified and stored. Only the company will mine. I'm hoping that data transparency and data integrity can be preserved by having a publicly visible blockchain but since there's no reward to users for mining there's not much reason they will actually mine.

How does a Generation block differ? What goes in the hashPrevBlock section of the generation block? All zeros?