I've always been perplexed by the way online games have always fought so hard to battle against the buying and selling of ingame currency. People will always find a way to circumvent restriction placed upon buying and selling items. I believe that games should just accept this fact and facilitate for players to buy and sell currency safely.
One way to accomplish this would be to put the entire currency onto the blockchain. Essentially you would be "mining" currency by playing the game. The next step would just be simply providing a gateway for people to trade the currency. This could be done with simply getting the currency listed on an exchange or creating your own gateway to facilitate exchanging FIAT for ingame currency. I'd almost equate this to like how you can buy currency in a mobile game except you would be buying directly from other players.
Setting up an easy to use system does end up with one large downside, bots. If money can be made in a video game, it's inevitable that people will try to do anything they can to exploit that. We already see bots in many other games, farming currency and items for profit, and most people despise their existence. Personally I've never seen them as much of a problem, the only reason they exist is because people are willing to pay for the product they offer and I've always viewed it as a similar activity to mining cryptocurrency. You are dedicating a computer to producing ingame items and currency for you, very similar to building a mining rig and tossing it in your basement if you ask me.
A system similar to what I'm proposing was used by Diablo 3 for a period of time. It wasn't on blockchain but there was a real money marketplace built right into the game. I absolutely loved it, I find something very satisfying about playing a video game all night and then cashing out my earnings to toss a few extra bucks into my wallet. During my time I paid back my initial purchase but not much else, leaving me with pretty much a free copy of Diablo 3. I was a bit surprsied when Blizzard decided to pull down the market because in their design Blizzard was taking a cut from every transaction and must have been raking in a huge profit for doing absolutely nothing. In the end I think there was some pushback from hardcore Diablo players stating that the auction detracted from the spirit of the game. In the end the Diablo 3 auction house was short lived and ended up getting taken down not long after going live.
On Novemeber 28, Valve will be releasing their new card game called Artifact and while this doesn't quite fit our intended model, it will have a full player driven market and ever card ingame will be purchasable for money through the Steam marketplace. Valve has allowed players to trade skins and other cosmetic items for their games before but as far as I know this will be the first time you can buy and sell items that actually impact their game. I think it will be interesting to see how this plays out because of the way it will create value for the game. I expect prices to steadily decline the longer the game is out, due to steadily increasing volume of cards especially with the games main mechanic being card drafts. Still the market should be comparable to Artifacts real world competitors like Magic: the Gathering. Magic has card values that change overtime as certain cards become relevant again and see sudden price jumps. I think we will be able to still learn quite a bit from Artifact just by observing how players use the market and how prices fluctuate over time.
In my opinion we are overdue for blockchain integration in a major video game release. I know that's a huge ask but having resources like Enjin tokens now available, we are moving towards that becoming a reality. Blockchains themselves are also improving and will soon be capable of handling the transaction volume that would be necessary to operate a game fully on blockchain. It's exciting to be part of this new emerging market and hopefully we will start to see many amazing new games and projects over the next year.