Ether Cards使用Chainlink VRF,为NFT实现新功能

"我们选择Chainlink VRF,因为它是业内最顶尖的RNG技术,为我们提供可验证公平性的防篡改随机数。Chainlink Labs团队也为我们顺利集成Chainlink VRF提供了巨大支持。"
Andras Kristof

Ether Cards创始人

Key results

since integrating Chainlink VRF

in total sales
unique Chainlinked NFTs purchased
2 days
to integrate Chainlink VRF

Ether Cards provides an advanced set of tools for creating any type of NFT. Ether Cards enables users to create dynamic cards that activate discounts, open up access, unlock features, connect to physical items, grant upgrades, and trigger changes based on real-world events, all within a single framework.


Ether Cards is a self-service platform that enables any project to add features, functions, gamification, community management, funding, and monetization strategies to their non-fungible tokens (NFTs).


Many of the teams using Ether Cards needed a tamper-proof and transparent source of randomness on blockchains to generate provably rare NFT traits, fairly distribute NFT drops, and introduce elements of pure chance to their projects.


Ether Cards integrated Chainlink VRF instead of building their own random number generator (RNG) or relying on currently flawed solutions, conserving time and resources and mitigating risks.

Business Outcomes

Connect Your NFTs to Verifiable Randomness



Ether Cards Sets Out to Add Pure Entropy to the NFT Experience

Non-fungible tokens (NFTs) surged in popularity as blockchain-based digital assets representing verifiable ownership of something completely unique. The initial crop of NFTs revolved around digital artwork with value that was largely derived from owning something that’s both rare and aesthetically pleasing. Although static digital art seeded initial interest in the NFT market, many early development teams recognized the much greater utility around connecting special features and privileges to NFT ownership, giving artists, businesses, and individuals a more expressive set of tools for creating meaningful and engaging experiences via NFTs.

Ether Cards recognized the early potential of dynamic NFTs and set out to build a universal framework for managing their entire lifecycle. With Ether Cards, users could launch NFTs as digital cards with custom artwork that have advanced utilities like special powers within games, limited-edition access to someone’s time, ownership claim to a physical asset, membership into private fan clubs, and various other built-in perks. Additionally, creators can also use Ether Cards to customize how dynamic NFTs are funded, monetized, managed, and distributed to the world. Upon developing the platform, the Ether Cards team quickly realized the importance of randomness within the platform, particularly because entropy brought excitement, meaning, and fairness to the NFT creation and gamification.


Existing RNG Solutions Showed Clear Vulnerabilities

  • Creating randomness in-house was costly, time-consuming, and complex
  • Randomness derived from blockchain data could be manipulated by miners
  • Randomness fetched from traditional APIs was centralized and opaque

Ether Cards initially considered building its own randomness solution. However, they quickly realized that this was not realistic, as it would divert resources to the development of backend infrastructure and require consistent maintenance. Ether Cards decided it was best to find an external source of RNG so it could solely focus on core platform offerings and working with creators on new NFT projects.

When Ether Cards began to explore randomness providers, they discovered that most of today’s existing solutions were flawed or exploitable. For instance, many RNG solutions derived directly from the blockchain data like block hashes were predictable and exploitable by blockchain miners via reorg attacks, essentially allowing miners to reroll in the hopes of getting more favorable results. Alternatively, RNG solutions derived from off-chain service providers were opaque, centralized, and didn’t offer clear evidence that the randomness they supplied was truly random. Relying on either of these solutions, especially as the value of NFTs scale, would put into question the integrity of various processes like random drops or randomized assignment of traits. Simply put, users had no way to verify that everyone was on a level playing field.

“Connecting Ether Cards to randomness was an especially challenging task since on-chain solutions can be exploited by blockchain miners and off-chain RNG providers are centralized and opaque. Trustless, verifiable randomness is essential for what Ether Cards is building.”

Andras Kristof
Founder of Ether Cards


Chainlink VRF: A Secure, Publicly Auditable Randomness Solution

Ether Cards integrated Chainlink VRF because it provided a verifiably tamper-proof source of randomness that was not subject to miner attacks and offered full auditability into the RNG process. Chainlink VRF works by combining block data with the oracle node's pre-committed private key to generate a random number and a cryptographic proof. Ether Cards' 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.

Ether Cards enjoyed several key advantages after integrating Chainlink VRF. First, Chainlink VRF uses block data that is still unknown when the request is made and cannot produce a valid cryptographic proof if tampering happens, removing blockchain miners ability to influence the outcome. Second, the Ether Cards smart contract will verify the cryptographic proof before accepting it, meaning fairness is automatically built into the application and doesn’t require manual verification. Finally, Chainlink VRF is powered by an open-source smart contract that makes cryptographic proofs publicly verifiable on-chain, allowing anyone to independently confirm the integrity of its code and each VRF request.

The result is Ether Cards having a true source of fair randomness. Ether Cards has been able to use Chainlink to enable a wide range of new NFT utilities for creators, such as provably fair distributions of high-demand NFT series, unbiased giveaways of limited edition NFTs, high-integrity algorithms that retain the scarcity at which rare NFT traits are assigned, and dynamic updating of select NFTs when certain real-world events occur. Ultimately, Chainlink VRF enhanced the Ether Cards platform by using unpredictability, chance, and transparency to create more valuable and engaging NFTs.

“After evaluating several RNG solutions, we identified Chainlink VRF as the most secure and easy-to-implement solution for our smart contracts.”

Andras Kristof
Founder of Ether Cards

Business Outcomes

Ether Cards Becomes a Leading Platform for NFT Creators

After integrating Chainlink VRF, artists, fans, and NFT collectors have increased trust in the integrity of core NFT processes like drops, giveaways, and trait assignments. The integration of Chainlink VRF was seamless and took only two days to complete, giving Ether Cards enhanced platform functionality in an extremely short amount of time. With Chainlink VRF, Ether Cards now has access to deeper collaborations with many new clients since any NFT project can use their platform to prove without a doubt that no one, not even the creators themselves, can influence randomness.

Since the integration, Ether Cards has sold over 6K cards for roughly $24M. Many of these sales came from high-profile companies collaborating Ether Cards and using Chainlink VRF to launch their NFTs. For instance, LaMelo Ball issued a dynamic NFT collection where Chainlink VRF was leveraged in randomized draws between participants to select the winners of LaMelo’s in-game shoes, custom arm-sleeves, and even his high school championship ring. Even more, Ether Cards was able to use their relationship with Chainlink to add an additional dynamic to LaMelo’s NFT collection where Chainlink oracles relayed to the blockchain that LaMelo won Rookie of the Year, which triggered the minting of a special set of NFTs.

LaMelo Ball the 2020-21 NBA Rookie of the Year issued a dynamic NFT collection using Chainlink VRF

2X Grammy-nominated artist and NFT creator Steve Aoki chose Ether Cards' Dynamic NFT technology to launch a series of collectible NFTs that feature clips from the upcoming stop-motion series Dominion X. It’s easy to see how new utility leads to increased demand in NFTs.

Check out this panel discussion to learn more about generating provably random NFTs with Ether Cards and Chainlink:

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