Remember the early days of blockchain gaming, when earning in-game rewards that could be sold for real money was all the rage? It was—and is—an awesome value proposition for blockchain. The problem was those early games focused too much on rewards and not enough on creating a great player experience.
But that’s changing. Game developers are making blockchain games that are actually fun to play. They’re also taking the innovation a step further—instead of just integrating blockchain for in-game loot as non-fungible tokens (NFTs), they’re designing games where the entire game logic is on the blockchain. With the entire game logic fully onchain (on a decentralized network of nodes), the game’s own community gains greater control over its future. No company can shut down the game by disabling its centralized server.
That’s where scalability comes in. If every part of the game is onchain—beyond just loot and basic moves like attacking and defending—transactions need to be near-instant and extremely low-cost. In this post, we’ll explain how that can be achieved on Ethereum.
Scalability issues in blockchain gaming
Ethereum and other popular Layer 1 (L1) blockchains often see a sharp rise in transaction fees during peak usage periods, making blockchain gaming prohibitively expensive. Slow transaction times add to the frustration, with players waiting minutes, or even hours, for in-game purchases or actions to be confirmed. This lag makes gaming less fluid and less enjoyable.
Scalability is the key to moving beyond simple play-and-earn models and toward more complex, fully onchain games that rely on frequent, low-cost transactions.
Understanding ZK rollups
Enter zero-knowledge (ZK) rollups, a Layer 2 (L2) scalability solution designed to make blockchain transactions cheaper and faster, without compromising security. ZK rollups accomplish this by offloading the heavy computation associated with transaction execution from L1 chains like Ethereum.
ZK rollups execute a batch of transactions on L2, and then produce a cryptographic proof (also called a ZK proof) that attests to the validity of the batched transactions. Only the proof and the state difference—rather than all the transaction data—are submitted to L1, reducing data storage requirements and computational load on the main chain.
To better understand ZK rollups, imagine a crowded bank where everyone has to wait in line for their transactions to be processed one at time. It’s chaotic and inefficient. Now imagine a legion of bank tellers gathering all the transactions and presenting the bank with a summary proving they were all handled accurately. This summary relies on ZK proofs, which verify that every transaction was carried out correctly without the bank needing to check every single one.
By bundling many transactions together and presenting a single proof, the bank could handle more tasks in less time, making the process faster and smoother. In the same way, ZK rollups allow for many blockchain gaming transactions to be processed efficiently while ensuring security and accuracy. This enables faster and lower-cost blockchain gaming transactions. On Starknet, for example, transactions are near-instant and were recently as low as $.005!
While other scalability solutions exist, such as optimistic rollups, ZK rollups stand out for their enhanced security. Unlike optimistic rollups, which assume transactions are accurate and only challenge them if proven otherwise, ZK rollups use cryptographic proofs to ensure that every state update sent to Layer 1 is valid.
A quick note: Although the term “ZK rollups” is used widely, most of these rollups aren’t focused on ensuring transaction privacy (i.e. proving computational integrity while revealing minimal information about users). Instead, they use proofs to verify the computational integrity of transactions executed on L2 while exerting as little computation as possible. Therefore, the terms “validity rollup” and “validity proof” are more accurate. Still, we’ll stick with the commonly used terms “ZK rollup” and “ZK proof” for the purposes of this post.
Benefits of ZK rollups for blockchain gaming
ZK rollups offer several advantages for addressing blockchain gaming scalability issues:
- Faster transactions: By executing many transactions on L2 before settling them on L1 at bundles, ZK rollups significantly increase the number of transactions that can be processed each second. This allows for smoother, more dynamic gameplay.
- Lower transaction costs: The L1 cost of processing transactions is spread across many transactions, reducing the per transaction fee. This enables microtransactions, enhancing the overall gaming experience.
- Better security: Because ZK rollups attest to the validity of all transactions with ZK proofs, they’re more secure than other rollups, such as optimistic rollups.
- Faster transaction confirmation: Reduced confirmation times allow for real-time interactions, minimizing the friction associated with blockchain transactions and ensuring a seamless gaming experience.
Case studies and examples
Let’s explore some examples of blockchain games built on Starknet, the validity rollup making any onchain game feasible on Ethereum. Influence, for example, is a massive multiplayer online (MMO) sci-fi game set in outer space in which players navigate an asteroid belt, build colonies, and engage in battles. Because it’s built on Starknet, Influence enables players to enjoy smoother gameplay, lower gas fees, and faster transaction speeds. This makes gameplay more accessible and dynamic, leading to a large player base and high levels of engagement.
Another example is the strategy-based, pay-per-session survival game Loot Survivor (launching soon on mainnet). Also built on Starknet, Loot Survivor players work their way up the leaderboard while enjoying fast-paced, fluid gameplay. These are just two examples of phenomenal blockchain games that leverage Starknet’s ultra-fast, low-cost transactions. Check out Starknet games
ZK rollups like Starknet empower players to interact with games in real-time, trading resources and managing their assets at a lower cost and without delays. As a result, player engagement in these games rises, operational costs drop, and developers can implement in-game features that would otherwise be unattainable.
Future prospects
What’s next for blockchain gaming? As ZK rollups get even faster and cheaper, they’ll pave the way for more complex blockchain games that put their entire logic onchain.
Starknet’s roadmap aims to build on its achievement of record-low fees with upgrades such as EIP-4844 compatibility (already implemented), as well as parallel transaction execution and block packing, features which were released in August ‘24. These improvements continue to lower transaction fees and boost throughput.
Final thoughts
ZK rollups significantly enhance blockchain gaming by lowering costs and speeding up transactions, while maintaining robust security. Starknet’s recent and upcoming upgrades, such as EIP-4844 compatibility, parallel transaction processing, and block packing, allow for hundreds of transactions per second with minimal fees.
ZK rollups benefit the entire blockchain ecosystem by efficiently handling more transactions. Volition and applicative recursion further reduce fees and enhance scalability, making blockchain even more suitable for broader use.
ZK rollups provide a practical solution to current blockchain gaming challenges. They allow developers to create more complex and engaging games without being held back by slow transactions and high costs. This drives growth in the industry and offers new opportunities for investors. ZK rollups hold the key to enhancing scalability and unlocking the full potential of blockchain gaming.
To learn more about game development on Starknet, check out DoJo, Starknet’s powerful gaming engine.
