Ether Cards to Integrate Chainlink VRF for NFT FeatureToken Launch 

By Mappo | EtherCards | 22 Mar 2021

Chainlink and Ether Cards

We are excited to announce that Ether Cards will be integrating with decentralized oracle network Chainlink to leverage its Verifiable Randomness Function. Chainlink VRF is a random number generator (RNG) solution built specifically for smart contracts, providing users with a tamperproof and provably fair source of randomness backed by an on-chain cryptographic proof that verifies the integrity of the process.

Chainlink VRF is right in the core of Ether Cards’ new platform. It is being used everywhere, starting with the inaugural FeatureToken Sale to ensure every NFT minted will have a set of provably rare traits, ranging from unique art drops to discount vouchers to free service tokens and beyond. 

Due to the value of unique traits with NFTs, an on-chain pseudo-random generation would have been extremely insecure. There are several technical horror stories of projects that used an insecure source randomness that eventually became vulnerable to frontrunning and other attacks. So Chainlink VRF actually made Ether Cards’ new incarnation possible.


Integrating Chainlink VRF Into the Ether Cards Framework

The Ether Cards framework allows anyone to maximize the usefulness and value of their NFT tokens by offering a set of tools and games that anyone can set up, and make NFT art and collectible cards (both individual places and series) much more enjoyable and engaging. Artists and marketplace owners can set up tickets, issue blind bags, create puzzles and other collectible puzzles, all with rewards and prizes that can be earned by users.

But the technology does not stop at gaming -- the underlying FeatureTokens system allows other projects to integrate the tech, and turn NFT cards into access cards, membership cards and discount vouchers for their particular project.

In order to maximize the value of NFTs, randomness is often a key element. However, accessing a secure source of randomness on-chain can be difficult. For example, on-chain randomness solutions can be subject to miner frontrunning, while off-chain randomness solutions are opaque and require trust in an off-chain data provider. These solutions do not provide adequate proof to users that they are indeed truly random and tamperproof, which becomes especially concerning as NFTs grow in value.

After evaluating several RNG solutions, we identified Chainlink VRF as the most secure and easy to implement solution for our smart contracts. Chainlink VRF works by combining a user-supplied seed with the oracle node’s private key to generate both a random number and a cryptographic proof. The cryptographic proof is key because it proves the integrity of the random number, showing that the VRF process was carried out in a tamper proof manner. By being tamperproof, users have clear on-chain evidence that the randomness underpinning the distribution and characteristics of NFTs was generated in a manner that is provably fair and unbiased. 

For more details on the math and reasoning behind Chainlink VRF, refer to the in-depth blog post: Chainlink VRF: On-chain Verifiable Randomness

Chainlink VRF explained
Beyond the Devcon VI ticketing, Chainlink VRF will become available within the Ether Cards framework for developers wanting to facilitate verifiably fair distribution of NFTs to random winners, as well as to generate provably rare traits within NFTs in a tamper proof manner. This will allow developers to build transparent features like ticket sales and puzzles where users don’t need to question the integrity of the winner selection process. Similarly, it enables developers to objectively assign various rarities and power levels to NFTs, where users can trust that everyone has an equal opportunity in earning higher value NFTs.

“Integrating Chainlink VRF is a major step forward in the progression of Ether Cards, especially with randomness being one of the key elements to creating value and fun within many gamified NFTS,” stated Ether Cards Founder Andras Kristof. “Chainlink VRF allows Ether Cards developers to provide unquestioned proof in the fair and tamperproof distribution of NFTs and assignment of traits, ultimately resulting in a maximization of user trust in the platform.”


About Chainlink

Chainlink is the most widely used and secure way to power universally connected smart contracts. With Chainlink, developers can connect any blockchain with high-quality data sources from other blockchains as well as real-world data. Managed by a global, decentralized community of hundreds of thousands of people, Chainlink is introducing a fairer model for contracts. Its network currently secures billions of dollars in value for smart contracts across the decentralized finance (DeFi), insurance and gaming ecosystems, among others.

Chainlink is trusted by hundreds of organizations to deliver definitive truth via secure, reliable data feeds. To learn more, visit, subscribe to the Chainlink newsletter, and follow @chainlink on Twitter.

About Ether Cards

Ether Cards is an NFT gamification and monetization platform. It helps artists to maximize the value of the art they create and helps NFT marketplaces keep their audience engaged.

Ether Cards is created and operated by a group of industry veterans who have a long professional history of supporting the biggest players in the space, including the Ethereum Foundation and Consensys.

Visit to participate in their grand opening, read for more information, and follow @ether_cards on twitter for rewards.

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aelf Head of Content - Cointelegraph Featured Author - Blockchain advocate


The EtherCards platform provides a suite of tools for NFT creators and marketplaces to monetize and gamify their art. The tools enable artists and marketplaces to turn items like collectibles, memorabilia, memberships, subscriptions, or tickets into their digital counterpart.

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