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Cometh Integrates Chainlink VRF To Help Mint Random NFT Cards Using Crafting Boosters

We’re excited to announce that Cometh — a blockchain-based strategy and space exploration game — has integrated Chainlink Verifiable Random Function (VRF) on Polygon mainnet. By integrating the industry-leading decentralized oracle network, we now have access to a tamper-proof and auditable source of randomness needed to create a random craft booster seed that is then used to generate a NFT card. Ultimately this creates a more exciting and transparent user experience, as all NFT cards are crafted in a fair and transparent manner.

Cometh Battle is a next-generation blockchain game with a novel in-game economic system. Players engage in galactic battles with strategies based on their deck of cards. The cards are not sold by Cometh but are crafted by players using the resources they hoard from winning battles. Players can also purchase cards crafted by other users. Cometh organizes tournaments and championships to bolster the community, all of which are free to play.

In order to craft and mint new NFT cards, Cometh needed access to a secure random number generator (RNG) that any user could independently audit. However, RNG solutions for smart contracts require several security considerations to prevent manipulation and ensure system integrity. For instance, RNG solutions derived from blockchain data like block hashes can be exploited by miners/validators, while off-chain RNG solutions derived from off-chain APIs are opaque and don’t provide users with definitive proof about the integrity of the process.

After reviewing various solutions, we selected ChainLink VRF because it’s based on cutting-edge academic research, supported by a time-tested oracle network, and secured through the generation and on-chain verification of cryptographic proofs that prove the integrity of each random number supplied to smart contracts.

Chainlink VRF works by combining block data that is still unknown when the request is made with the oracle node’s pre-committed private key to generate both a random number and a cryptographic proof. The Cometh smart contract will only accept the random number input if it has a valid cryptographic proof, and the cryptographic proof can only be generated if the VRF process is tamper-proof. This provides our users with automated and verifiable assurances directly on-chain that the card crafting mechanism is provably fair and was not tampered with by the oracle, outside entities, or the Cometh team.

“NFT cards lie at the core of our strategy game, enabling players to customize their strategy and compete with one another competitively. We’re excited to be able to generate our NFT cards in a provably fair and transparent manner using Chainlink VRF.” — Vincent Le Gallic, CTO

About Chainlink

Chainlink is the industry standard for building, accessing, and selling oracle services needed to power hybrid smart contracts on any blockchain. Chainlink oracle networks provide smart contracts with a way to reliably connect to any external API and leverage secure off-chain computations for enabling feature-rich applications. Chainlink currently secures tens of billions of dollars across DeFi, insurance, gaming, and other major industries, and offers global enterprises and leading data providers a universal gateway to all blockchains.

Learn more about Chainlink by visiting or reading the developer documentation at To discuss an integration, reach out to an expert.

About Cometh

Cometh creates blockchain games running end-to-end on smart contracts that easily integrate with DeFi protocols.

Cometh innovates by leveraging the unique features of the blockchain to foster entertainment and to propose the best gateway to Web3.

With a first version of the game deployed in February 2021, Cometh rapidly became the most active blockchain game.

For more Cometh updates and discussions:

Website | Discord | Twitter| Telegram | Instagram



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Cometh is a groundbreaking strategy game where players can win valuable tokens and that leverages the Decentralized Finance ecosystem