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Thursday, December 7, 2017

Breeding Digital Pets on the Blockchain

The new game CryptoKitties is a fascinating way to play with trading actual assets over the blockchain instead of just currency.

The most popular thing in cryptocurrency right now is a game called CryptoKitties, that lets users buy, breed, and sell cartoon cats on the Ethereum Blockchain.

On the surface, it looks like nothing incredibly unique, but how it works using a blockchain in the background makes CryptoKitties interesting.

In-game purchases and markets are not new. Games like World of Warcraft and others have markets for in-game assets. But in every case up until now, the relationship between a user and a game was like that of a customer and a bank. You held and could use the assets in the game so long as the game let me, but you didn’t truly own the asset.

Since CryptoKitties (CKs) live on the Ethereum blockchain, when you pay Ether to buy a CK you trade for the key to the CK token which you from then on own and can choose to do what you want with.

Playing with something as simple as CryptoKitties allows you to experience what it means to be able to trade ownership of a good over a blockchain. The digital signature for the kitty that you possess works like its genome and is responsible for the characteristics you see when you use the CK interface. When you breed CryptoKitties, the offspring is created with some variation of the characteristics of the two parent cats.

New CryptoKitties are created regularly and denominated by their generation. Gen 0 being newly spawned by the network and not bred.

Having provable ownership of your CryptoKitties creates some interesting possibilities. You have the ownership keys and that ownership can’t be revoked, no matter what the makers of CryptoKitties decide.

Since your ownership keys are in your wallet, and not on an in-game ledger, you can trade or use them outside of the game. You could make a deal in person with a friend, or send it to a friend in China like you would with any cryptocurrency transaction. Since you can prove you have your CryptoKitty keys, 3rd parties can create applications that make use of the same identifying keys, allowing you to use your CKs outside of the actual CK interface.

In CK the developers control the emission rules for new CKs so they could increase the supply, but they cannot replicate, revoke, or re-assign ownership. Instead of having to trust the developer to respect your claim to in-game goods you truly do own them.

It is gimmicky, but it currently accounts for $1M+ in trade and more than 10% of all the transactions on Ethereum and its only been out for 4 days (as of Dec. 4)!

There has been a lot of theorizing about the potential of digital assets on blockchains. Playing with something as simple as CryptoKitties allows you to experience first hand and wrap your head around some of the possibilities about what it means to have provably unique digital assets and to be able to trade ownership of a good (instead of just currency) over a blockchain.

If you’re curious about it CryptoKitites, here are a few more resources:

Reprinted from