Our Wasm smart contracts have been deployed and are now live on the Shibuya testnet! Shibuya is a testnet of Shiden/Astar Network. Currently, the gameplay is the same as our PrototypeNet, which has been playable since before.
Smart contract 
But why are we building the new smart contracts while we already have our PrototypeNet? What are the differences?
This game was initially built as a standalone chain, and that’s the PrototypeNet. At that time, the Wasm smart contract development environment was not mature enough yet, so we developed the independent chain on a Substrate blockchain framework.
Since then, the ecosystem and toolset have evolved a lot, and it allows us to have a contract implementation, that is deployed to other smart contract chains. Our current focus is on the smart contract architecture.
By building smart contracts, we can rely on well-established chains, like Shiden. This brings several benefits, including more decentralized infrastructure and better accessibility from the broad community. On the other hand, only chains can have low-level runtime features. Hence, some UX improvements around transactions we’ve made for our chain can’t directly be applied to contracts, but we can address it with other technical solutions.
Our contracts are implemented as Wasm smart contracts, using Rust language with ink! DSL. Wasm contracts in the Polkadot ecosystem are actively developing now, and it’s not launched on mainnet yet. Ethereum Virtual Machine (EVM) is widely used for contracts now, but the new Wasm contract architecture has some advantages. We ported the Rust codebase of our chain into contracts, and both implementations share the same source code.
Further development 
What we’ve done here is to confirm the technical feasibility. Next, we’ll upgrade the gameplay and deploy it on Shiden. The first gameplay event round will be held there with SDN prizes. The SDN has been accumulating in our treasury from Shiden dApp staking rewards.
Try on testnet 
You can try our smart contracts on the Shibuya testnet. You need test token SBY to cover gas fees, so claim it on the faucet first following this guide. The rule of the game is the same as PrototypeNet, but you’ll see the network changed to the contract testnet while signing transactions. Please access the game from this link. It shows the network name on top of the screen.