Cryptocurrency-based gaming is growing up.

Gods Unchained, an upcoming trading card game (TCG) based on Ethereum, has released its first gameplay trailer, and it looks great.

On the surface, Gods Unchained is a clone of Hearthstone, Blizzard's game that made the genre immensely popular after it launched in 2014. You collect cards, which give you various traits and abilities, build a deck, and then try to defeat opponents in turn-by-turn play.

But the game is different in one key aspect — its cards live as non-fungible tokens on the Ethereum blockchain. Non-fungible tokens or NFTs are cryptographic tokens which are unique, contrary to fungible tokens (think ethers or bitcoins) which are all exactly alike and interchangeable (for technical details, go here).

This means that once you purchase a Gods Unchained card (which you can easily do with ether, Ethereum's currency), it's literally yours — no one can alter it (unless the code of the smart contract that defines it allows it). This trait should resonate with gamers who are annoyed by Blizzard's constant changing of Hearthstone's rules, with certain cards being nerfed (i.e. made less powerful) and others boosted in order to balance gameplay.

Fuel Games, the Sydney-based company behind the game, received a $2.4 million seed round of funding in May, with Coinbase Ventures participating. It also created quite a bit of buzz among would-be-players, who spend tens of thousands of dollars on rare cards well before the game's planned launch. In total, the company says it sold over 1.5 million cards.

To date, we’ve sold over 1.5 million Gods Unchained cards to thousands of gamers all around the world. We are so excited to finally show them what we've been working on. — Gods Unchained (@GodsUnchained) November 15, 2018

Games based on non-fungible Ethereum tokens aren't new; one often cited example is Cryptokitties, a digital kitty trading card game whose popularity brought Ethereum's network to a screeching halt earlier this year. But Cryptokitties (which recently received a big round of funding of its own) is quite a simple affair, while Gods Unchained appears to be fully-fleshed out with beautiful graphics and tons of features.

The game is also different in the way it interacts with Ethereum's blockchain. In Cryptokitties, everything happened on the blockchain; with Gods Unchained, the gameplay takes place on the company's servers. This means that the game should probably perform well and not clog Ethereum's network once it goes live — but it also means it's not very decentralized, which is an important trait of many Ethereum-based projects.

CoinDesk reports that the game will enter a closed beta period in the "next couple of weeks," during which the players who have pre-ordered cards will be able to try it out. A three-month open beta period is scheduled after that, followed by a full launch.

Disclosure: The author of this text owns, or has recently owned, a number of cryptocurrencies, including BTC and ETH. The author is also quite sure he had once purchased some Gods Unchained cards, but for the life of him, he can't find them now.