Chainlink VRF is the industry-leading secure random number generator (RNG), enabling smart contracts and off-chain systems to access a verifiably tamper-proof source of randomness. Since its mainnet launch in October 2020, Chainlink VRF has serviced over a million requests for fair and unbiased random numbers across Ethereum, Polygon, and Binance Smart Chain. Those random numbers have been used to power a wide variety of use cases in blockchain gaming, NFTs, and DeFi.
In this blog post, we briefly explore how Chainlink VRF works and its advantages over existing RNG solutions, before looking at 35 unique use cases powered by Chainlink VRF that are in production by top projects or waiting to be created by innovative developers.
Why Chainlink VRF
When people initially think of gaming, NFTs, art, and even science, they often overlook the importance of randomness in determining outcomes. From selecting patients in random controlled trials to determining winners in games to generating variation in digital artwork, entropy is a core component to making these processes fair, exciting, and secure. Yet, accessing a source of randomness that is tamper-proof, unpredictable, and auditable by all participants is not an easy task—especially when bringing entropy into highly deterministic blockchain networks.
For example, RNG solutions derived from the blockchain itself, such as using block hashes, introduce attack vulnerabilities where blockchain miners/validators can choose to publish a block only when it generates more favorable results for themselves. Essentially, miners/validators have the ability to re-roll the dice to obtain a new source of randomness.
Alternatively, RNG solutions derived from off-chain API providers are opaque and unverifiable, so users have no proof that the randomness was not manipulated. There is no way to tell the difference between true or manipulated randomness, leading to a great reduction in trust. Both solutions become increasingly concerning as the amount of value being secured by the RNG solution goes up.
Chainlink Verifiable Random Function (VRF) overcomes these limitations using off-chain oracle computation and on-chain cryptography. 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 consuming application will only accept the random number input if it has valid cryptographic proof, and the cryptographic proof can only be generated if the VRF process is tamper-proof.
Thus, Chainlink VRF provides users with automated and publicly verifiable proof that the randomness supplied is provably fair and was not tampered with or predicted by the oracle, blockchain miners, external entities, or the application’s development team. Moreover, Chainlink VRF is powered by fully open-source code and all cryptographic proofs are verifiable on-chain by anyone. If you want to learn more about the mathematics and cryptography behind it, view the Chainlink VRF technical blog post.
Ultimately, the ability to access a fair and unbiased source of randomness in a verifiably secure manner enables blockchain developers to build a whole new set of applications for blockchain gaming, NFTs, lucky draws, marketing campaigns, fan rewards, and fair selection and security processes.
To showcase to developers how to apply provably fair randomness within applications, below is a list of 35 ways to use Chainlink VRF. If any of these ideas resonate with you or you want to learn more, find us on Discord and check out the developer documentation to begin building with Chainlink VRF today.
Blockchain-based games are redefining the $175 billion traditional gaming industry because they are built upon secure, fraud-proof infrastructure while retaining cutting-edge features and graphics. The blockchain gaming industry has begun to grow in popularity due to its global accessibility, play-to-earn opportunities, and provably fair gameplay, leading to more competitive, financially rewarding, and meaningful user experiences. Chainlink VRF is integral to bringing secure entropy to blockchain games and the growing metaverse they operate within.
Start Building With Transparent Randomness
Most games have various characters, each with their own unique traits. Some characters are common while others are very rare. Determining how new characters are distributed to users is critical to fair gameplay, especially in blockchain gaming where certain characters can earn users higher financial rewards.
Axie Infinity is one of the most popular play-to-earn blockchain games, where users battle, raise, and trade NFT characters known as Axies. Each Axie consists of six parts—the back, ears, eyes, horn, mouth, and tail—with each having different base statistics and possible traits. Since certain characteristics are more valuable than others, Axie Infinity integrated Chainlink VRF to help ensure that each of the 4088 Origin Axies minted into existence had a truly random set of characteristics based on the predefined odds stated in their smart contract.
ChainGuardians is another play-to-earn blockchain game set in a sci-fi cryptoverse. Players can collect Guardian NFTs, form alliances, and battle one another in a novel role-playing game (RPG). ChainGuardians integrated Chainlink VRF to enable players to randomly mint 1 of 16 unique Chainlink Guardians NFTs with various colors. These customized characters require a bit of chance to obtain, yet create a more personalized gaming experience for players.
Matchmaking Players in PVP Battles and Tournaments
Matchmaking is a critical component of multiplayer games involving player versus player (PvP) battles, whether it’s a single, one-off battle or tournament style. The success of players and their opportunities to earn rewards can come down to the caliber of opponents they are assigned to battle, making it important to remove bias and predictability from matchmaking algorithms.
CryptoBlades is an immersive, NFT-based blockchain game where users can craft unique items, defeat monsters, participate in raids, and battle against one another in PvP combat. One of the many ways CryptoBlades utilizes Chainlink VRF is to establish unpredictable battle pairings, with the victors taking home SKILL token prizes. Thanks to Chainlink VRF, players have confidence that there are no special backdoor privileges or manipulated pairings to any one player’s advantage.
Generating Loot Box Contents
Loot boxes are a unique way to make powerful weapons, limited-edition equipment, special power-ups, and other rare content available to players. A loot box is a consumable virtual item that users redeem their real or in-game currency for in order to earn a chance to win new items. Loot boxes may contain highly sought-after items, so tamper-proof randomness is important to fair loot box distribution models.
MTVE is a massively multiplayer online role-playing game (MMORPG) that takes place in a science fiction setting. Players can control spaceships, own planets, explore a vast metaverse, battle one another, and trade in-game items with others. MTVE integrated Chainlink VRF to assign ships initial characteristics and create randomized loot boxes, offering users the opportunity to receive high-value gear.
Evolution Land is a sprawling metaverse developed by Darwinia Network, where gamers can mine resources, trade with other users, govern different continents, and own NFT-based characters known as Apostles. Evolution Land is integrating Chainlink VRF to fairly distribute in-game prizes as random rewards when players open treasure boxes or breed Apostles.
“We’re excited to make Chainlink VRF part of Evolution Land, and believe that this integration of randomness will help us in our mission to create a complex, economically rich game experience that users can independently verify as true and unbiased.”
– Denny Wang, Co-founder of Darwinia Network
Honoring Odds-Based Games
Certain types of games are based purely on odds and chance rather than a user’s input, skill, or experience level. For example, Blockmine integrated Chainlink VRF to support their upcoming game Next Card, a game where people try to determine which card will be drawn next for a chance to win prizes.
Additionally, racing games often involve a mix of odds and randomness too. DeRace is an on-chain virtual game where users collect, breed, and race NFT-based horses to win prizes. Instead of the best attribute horses always winning competitions, DeRace is integrating Chainlink VRF to randomize race outcomes. Before starting a race, the smart contract will compare each horse’s traits against one another to calculate their odds of winning. Chainlink VRF will then select a random winner based on those probabilities for a more fun and unpredictable experience.
As players reach objectives and progress in a game, they are often given upgrade opportunities as rewards for their achievements. Instead of having the same upgrade for each user after common milestones, games can create unpredictability by introducing a set of upgrades determined by chance.
Gaming platform BORA will represent all in-game items, land, and characters as NFTs in its upcoming title release of BORA Island 2.0. BORA plans to utilize Chainlink VRF to randomly reward users with unique in-game items when they pass particular objectives or even entirely new upgraded characters via community reward programs. With Chainlink VRF, BORA Island 2.0 players can rest assured that each participant who has fulfilled the specified requirements will have a fair chance at receiving the best in-game upgrades.
Generating Maps and Placing Items on Maps
While many games have fixed maps, there are new opportunities for algorithms to generate new lands and various features within a landscape. Randomness can be applied to these algorithms to select from a list of possible outcomes or even function within item placement and background displays in augmented and virtual realities. How items are distributed to players contributes largely toward fair gameplay, which is a key factor in cultivating a global ecosystem of active players.
OVR is an open-source, augmented reality (AR) game where players can merge their physical world with a virtual world to unlock unique experiences, visualizations, and prizes at different geographical locations. The OVR AR world is split up into 300 OVRLand NFTs representing 300 square meters in the real world. Owners of these NFTs can customize experiences and visualizations for other users who happen upon their territory. At the same time, players may also encounter treasure chests and other unique events as they explore the metaverse.
One of the main reasons OVR integrated Chainlink VRF was to spawn special items and experiences in unpredictable locations. OVR used Chainlink VRF in their recent treasure hunt to randomly place treasure chests in OVRLand, helping create a metaverse where everyone has a fair chance to collect prizes.
Powering Critical Hits
Instead of basing games purely on deterministic inputs and outputs, developers often assign odds to certain actions that can depend on player and opponent skill levels, equipment, character traits, environment, and so on. This is especially common in fighting games with striking—the chance a user has to hit an opponent—and critical hits, where players have more damaging attacks.
For instance, a weak opponent may have only a 15% chance to carry out a strike against a stronger opponent, while a special sword may boost their chances by 5%. The most competitive and rewarding games generate input and output randomness so that even the most experienced players have a chance of being on the wrong side of luck. Chainlink VRF provides a way to determine outcomes based on preassigned strike and critical hit ratios.
Determining Turn Order
Though seemingly innocuous, players can gain advantages in turn-based games based on player order, particularly as more players become involved. Even if the advantages are small, little changes in odds based on player order can make a difference as more value is on the line. Randomness offers a way to equal the playing field by leaving ordering up to chance.
One of the first games to launch on the Avalanche blockchain was Avaxcells—NFT trading cards that gamers can use to battle one another in 1v1 PvP combat. Each Avaxcell NFT minted features 1 of 8 element specials, such as fire, water, and wind, which has unique benefits and disadvantages against other elements. Each card also has a cell type, such as common, special, rare, epic, and legendary, that indicates the strength and rarity of the NFT. Avaxcells is integrating Chainlink VRF to fairly determine which player gets to attack first in a PvP duel, eliminating any potential dispute about ordering.
Spawning Character Locations
When a user dies in many first-person shooter (FPS) games, they are then respawned on the map somewhere, usually within a set few locations. Additionally, portals in games can spawn players to new lands that may offer certain advantages depending on their location. Randomness offers a way to inject unpredictability into determining new character locations.
Fabwelt is a blockchain gaming platform featuring a FPS game called Arsenal and a fantasy sports game called Fanwelt. One unique aspect of Fabwelt’s games is that users can influence the gameplay by obtaining NFT tokens that then alter rules and settings and award special power-ups and abilities. In first-person shooter games such as Arsenal, character placement is a notoriously complex process, as more experienced gamers can memorize spawn points and camp near them to attack players as soon as they respawn. Since this is an uncompetitive gaming dynamic, Fabwelt is integrating Chainlink VRF to ensure that character placement and starting points are arbitrary and unpredictable.
Creating Unpredictable Game and Augmented Reality Scenarios
Unpredictability is a major part of what makes games fun—if a user were able to know exactly what was going to happen in each situation, they would be less likely to continue playing the game. Thus, unpredictable events in the metaverse or unexpected bosses that need to be defeated add elements of excitement to gaming.
Sportemon Go is an interactive ecosystem for everything sports, gaming, and NFTs. Sportemon Go features an AR world where users can collect, trade, and discover NFT trading cards representing their favorite sporting heroes across various professional leagues. Sportemon Go is integrating Chainlink VRF to randomly distribute NFTs to users as they explore their surroundings and engage with the platform, bringing more excitement to their AR world.
For more information on how Sportemon Go is using Chainlink VRF in their sports application, watch their Chainlink Live interview:
NFT Creation and Distribution
NFTs have emerged as one of the leading use cases in the blockchain industry, mainly due to their novel ownership features where users have complete control and ownership over unique digital assets. Though many first-generation NFTs have revolved around digital artwork, NFTs are quickly becoming more gamified through the use of oracles that enable them to use external data and computation to affect their generation, distribution, and ongoing appearances. Below are just a few of these “dynamic NFTs” that leverage Chainlink VRF for enhanced utility and fairness.
Connect Your NFTs to Verifiable Randomness
Assigning Uncapped NFT Traits Using Probability
Similar to Axie Infinity, NFTs are often generated upon minting based on the probability of receiving certain traits from a set of characteristics. For example, Polychain Monsters is a blockchain-based game inhabited by NFT-based monsters with three distinct categories of characteristics—color, horn types, and glitter—and several traits with varying rarities within each category. The combination of traits across all three categories ends up defining the rarity of the Polychain Monster.
Since the rarity of the Polychain Monster determines its power in battles within the Polyverse, it’s critical to have a fair and transparent source of randomness during the generation of Polychain Monster NFTs. It’s why Polychain Monsters integrated Chainlink VRF, so that when users purchase booster packs, the Polychain monster NFTs they receive are generated in a completely random way. Not only does Chainlink VRF create a fair distribution model, but it protects the integrity of the probabilities for traits, given there is no fixed supply. Thus, no one can exploit the minting algorithm to generate the rarest Polychain Monster, such as the Ultra Rare Bitcoin Dragon, with a drop rate of only 0.01%.
Polychain Monsters set the record for the largest number of Chainlink VRF calls by one project, generating over 520,000 NFTs in just under 14 days.
These traits don’t just apply to characters in games though, but can also apply to characteristics of art. CryptOrchids is a dynamic NFT art project, where the NFTs can change over time to reflect the real-world growth and impermanence of flowers. Users need to water their CryptOrchids weekly within a specific 3-hour time window or else their flower NFT will die. CryptOrchids uses Chainlink VRF to determine the species of newly minted flower NFTs, with each breed having a set rarity. For example, the Shenzhen Nongke Orchid has a 1 in 10,000 chance of being minted, which is extremely rare since the total collection of CryptOrchids is capped at 10,000. However, the use of probability means more than one Shenzhen Nongke Orchid is still possible.
Distributing a Fixed Cap Supply of Traits
While some projects have an open-ended supply of each trait and rely on probabilities to keep those traits scarce, other projects implement a fixed supply of NFT traits that eventually run out once they are minted into existence. By capping supply, a sense of true scarcity is introduced that can even increase over time as the supply of remaining non-minted NFTs dwindles down. Chainlink VRF can be used to uphold the probability of receiving rare items to create a high-integrity distribution method for fixed supply NFTs.
Awarding Real-World Prizes to NFT Holders
NFTs can also represent exclusive access to real-world prizes and rewards, where only NFT holders are eligible to win. Through a partnership with Ether Cards, LaMelo Ball became one of the first professional athletes to offer dynamic NFT trading cards to his fanbase. The highest tier of his NFT release, the Gold Evolve cards, automatically enter holders into random draws to win memorabilia such as his in-game shoes, custom arm sleeves, and his high school championship ring.
LaMelo’s NFT collection used Chainlink VRF to select winners of these draws and Chainlink oracles to mint special NFTs dependent on whether or not he won the 2021 NBA Rookie of the Year award. LaMelo did win and Chainlink oracles delivered the results on-chain to trigger a mint of the Rookie of the Year NFTs for Gold Evolve holders.
Since integrating Chainlink VRF, Ether Cards has seen over $24M in total sales, including 6K+ unique Chainlinked NFTs purchased.
Rewarding Community Members and Celebrating Milestones
Another way to use NFTs is to create communities consisting of owners of the NFT, particularly useful when there is a fixed supply. In order to foster community and shared goals, NFT projects can release random NFT rewards or upgrades to community members only. These rewards can also be based on hitting certain milestones or commemorating special events.
Bored Ape Yacht Club (BAYC), one of the top 10 NFT projects according to DappRadar at the time of writing, features a collection of 10,000 NFTs representing APE-inspired artwork. BAYC NFT holders also gain access to members-only club features such as THE BATHROOM, a collaborative graffiti board. BAYC used Chainlink VRF to randomly distribute their new Mutant Serum NFTs to current BAYC NFT holders, giving users the ability to mutate their Bored Ape into a new, limited edition NFT. When asked why Chainlink VRF worked, the BAYC team stated:
“Because the Serum type metadata was loaded onto the contract before we used Chainlink VRF to generate the random starting index for the collection, nobody—including ourselves—could have known which Serum types would end up corresponding to which BAYC IDs once the starting index was computed.”
Polkawar is a gaming platform featuring a native fighting game and an NFT marketplace where users can buy and sell items, weapons, and equipment to help them become the strongest fighter. Currently, users can select characters ranging from an NFT-based Warrior, a Magician, or an Archer and equip them with different weapons, including a sword, a tessen, and a scepter. Polkawar is integrating Chainlink VRF for a verifiably fair way to distribute the initial set of 10 items to users participating in their airdrop program, helping ensure everyone has an equal opportunity at receiving the rarest items.
Fundraising for Charities
NFTs provide a great mechanism for charity fundraising, as users can receive limited-edition NFTs based on their contributions that give them opportunities to win prizes. One of the unique advantages of the NFTs is that they can be easily sold on secondary markets or simply transferred to friends who may be more interested in the reward.
NFT platform UREEQA integrated Chainlink VRF to release a limited edition set of baseball trading card NFTs inspired by MLB baseball player and cancer survivor Trey Mancini. All of the proceeds from the sale went directly to the Trey Mancini Foundation to support cancer patients. Chainlink VRF was used to randomly assign 100 out of the 500 total NFTs to receive special perks like in-game tickets and memorabilia.
Facilitating No-Loss Battle Royales
Instead of having various probabilities during miniting, projects can gamify the assigning of rare NFT characters through no-loss battle royales. A no-loss battle royale is a game where NFT holders battle tournament style to see which NFT is the last one standing, with the winner earning an upgrade to their NFT. Picking winners each round necessitates a fair source of randomness, especially when winning increases the value of the NFT.
Nifty Royale is a gamified NFT platform enabling users to purchase limited edition original artwork drops and pit them against opponents in exciting Battle Royales for a chance to win additional or upgraded artwork. In Nifty Royale, users compete in multi-round elimination games where each player has a 50/50 chance to win and the game doesn’t stop until only one NFT remains. Nifty Royale integrated Chainlink VRF to settle each round.
“We initially built Nifty Royale during the 2021 Spring Chainlink Virtual Hackathon as an idea to challenge the traditional rarity qualities of existing NFTs. Through Chainlink VRF, we now have a tamper-proof source of on-chain randomness, enabling users to win rare NFTs through a provably fair and unbiased last-NFT-standing battle royale.”
– Tim Nan, Co-founder of Nifty Royale
Lucky Draws and DeFi
Lucky draws are a core part of the blockchain gaming industry, as well as increasingly being used within DeFi protocols to bootstrap additional gamification features. They serve as a way to give away random rewards to community members or simply offer a form of entertainment. Below are some of the various ways projects use Chainlink VRF to conduct provably fair lucky draws and to gamify DeFi.
Picking Winners in No-Loss Prize Games
No-loss prize games are similar to prize-linked savings accounts in that they offer users the chance to save their money, while potentially winning valuable prizes without the risk of losing their deposit. Typically, no-loss prize games take user deposits and invest them in interest-bearing instruments, which collect interest over time. The cumulative interest is then randomly distributed to a small number of users and everyone else is able to withdraw their original deposit.
PoolTogether is a decentralized, open-source protocol offering novel no-loss prize draws that resemble prize-linked savings accounts (PSLAs). With PoolTogether, users can participate in PoolTogether’s DAO-managed no-loss games or create their own without any permission. PoolTogether integrated Chainlink VRF to select winners from weekly no-loss pools, helping ensure winners are chosen fairly based on their initial deposit amount. After integrating Chainlink VRF, PoolTogether awarded over $4M in prizes and has had more than 2400+ people participate.
Minting Random NFTs with Staked DeFi Tokens
One way DeFi projects have benefited from randomness is having their tokens used in gamified ways while still allowing users to retain asset exposure and earn yield. Aavegotchi is a blockchain-based game featuring rare and collectible digital pets with unique traits such as aggressiveness, spookiness, energy, and more. Users can purchase portals to generate one of the ten different Aavegotchi NFTs based on randomness supplied by Chainlink VRF. Aavegotchi is unique, though, in that all of their NFTs are claimed by staking aTokens (Aave liquidity pool tokens), creating a novel gaming experience where users generate interest as they interact with the ecosystem. Aavegotchi owners can then use their NFTs, which have different powers, in various games to earn additional rewards such as Gotchi Tower Defense and SushiVader.
Shortly after integrating Chainlink VRF, Aavegotchi became a top-10 NFT project according to DappRadar, registering over 500,000 user transactions and $14M in volume on their platform.
Check out the Aavegotchi case study to learn more: https://chain.link/case-studies/aavegotchi
Choosing Winners in Win-Win Gamified DeFi Protocols
Another way teams have implemented lucky draws is within DeFi protocols, such as giving select participants additional yield rewards based purely on chance. One such protocol gamifying DeFi is Beefy Finance, a multi-chain yield optimization protocol. Beefy Finance offers a win-win prize pool game called Moonpot, where users can buy tickets to earn a percentage of all the aggregated yield from various pools in addition to the yield earned on their assets. Moonpot integrated Chainlink VRF to fairly distribute the additional yield rewards.
Determining Winners in Custodial Draws
In a custodial draw, users deposit their assets with a custodian who then distributes prizes at the end. Since custodial drawings have historically been opaque, a cryptographically provably source of randomness can bring unprecedented transparency to the process, including within state lotteries or even national Green Card lotteries.
Bitrue is a digital assets exchange that offers a Daily XRP Raffle. Users participate by purchasing tickets, selecting 5 numbers, and hoping they match the winning numbers. Even if players don’t manage to match all 5 numbers, they still receive prizes for getting 3-4 numbers correct or guessing the final number. Bitrue integrated Chainlink VRF to outsource their RNG to a blockchain-based solution to bring new levels of public auditability to centralized draws.
Selecting Winners in Non-Custodial Draws
Instead of involving a custodian, non-custodial draws use decentralized smart contracts on blockchains to hold funds in escrow and release them when certain parameters are met. For non-custodial draws, randomness is often used to directly determine how locked up funds are distributed to users, involving no manual input. Non-custodial draws can use Chainlink VRF to help ensure each winner is determined in a transparent and unbiased manner.
Randomizing Rebase Times
A specific type of DeFi project that can benefit from randomness is rebasing tokens, which increase or decrease their supply at regular intervals based on certain conditions. Rebases often occur to incentivize certain market activity, such as rebalancing of a stablecoin so it maintains its peg. However, when the time of the rebase is always known, it can fuel unwanted speculation and short-term volatility. Instead, rebasing tokens can incorporate an element of randomness to smooth over some of the volatility by making the exact time of the rebase unpredictable yet still keeping it on a relative schedule.
Gamifying Yield Farming Rewards
In most yield farming protocols, users deposit liquidity to a pool and receive an estimated annual percentage yield (APY). APY is often the same for all users in the pool and depends on the pool’s total size of deposits. However, some yield farming protocols are gamifying their reward systems to establish varying APYs between users, creating excitement for users, often through the element of randomness.
Block Ape Scissors is a novel yield farming and gaming protocol where users can deposit funds to staking pools or engage in play-to-earn games like Rock Paper Scissors to earn exclusive rewards and NFTs. Block Ape Scissors is integrating Chainlink VRF to randomize interest rewards in their yield farming pools. Once a user deposits funds to a pool, the Block Ape Scissors smart contract calls Chainlink VRF to assign a provably random daily percentage yield (DPY) to the user.
Marketing Campaigns and Loyalty Rewards
Another fascinating way to use randomness, both for NFT projects and traditional companies, is to randomly reward participants in customer loyalty programs or when certain marketing accomplishments are reached. Loyalty rewards programs incentivize return customers while incentivized marketing campaigns help focus communities around specific milestones, benefitting companies and customers. Chainlink VRF can help distribute random rewards to drive more targeted market campaigns and keep existing customer bases engaged.
Conducting Random Giveaways to Event Participants
Companies also aim to drive up participation in events by offering random rewards to those physically in attendance or those simply engaging with them online. With Chainlink VRF, participants can get that extra bit of trust in the process, ultimately driving up more excitement and engagement for the event.
Illuvium is an open-world adventure game that allows players to explore a sprawling sci-fi universe and participate in PvP combat using their collectible character NFTs, known as Illuvials. Each Illuvial can be 1 of 5 classes, including Empath, Fighter, Guardian, Rogue, and Psion, and also have 1 of 5 affinities, including Air, Earth, Fire, Nature, and Water. To engage their fans prior to the start of an upcoming yield farming event, Illuvium integrated Chainlink VRF to reward a lucky community member with a limited-edition Illuvial.
Watch Illuvium’s interview on Chainlink Live to learn more about their game and how they leveraged Chainlink VRF:
Giving Random Rewards to Loyalty Club Members
A common method to facilitate loyalty rewards programs is by having a membership club that offers various perks and rewards, such as access to exclusive events, product discounts, or merchandise. Companies can use randomness to give away awards without bias.
ApeSwap is a multi-purpose DeFi platform offering users a DEX, liquidity vaults and farms, and non-fungible apes (NFAs), their own version of NFTs. As a way to reward their dedicated community members, ApeSwap enters all holders of NFAs into their “Saturdays are for the NFAs” program, where all NFA holders are automatically eligible to win BANANA rewards in weekly draws. The ApeSwap team removed themselves from the winner selection process by outsourcing it to Chainlink VRF, leading to happier, more engaged Apes.
Distributing Random Rewards When Marketing Targets are Hit
The successes and failures of marketing campaigns are often judged quantitatively, such as the number of users engaging with posts, the number of “likes” or “dislikes,” or whether there was an increase in followers. Companies can drive up engagement for marketing campaigns by issuing rewards that are based on outcomes, even having multiple tiers to drive increased interest to reach higher rewards. However, it’s often not clear whether the rewards at the end of campaigns are truly fair, or if there are increased probabilities for insiders—the McDonald’s Monopoly game being one such example.
However, if individuals knew that campaigns were forced to behave honestly, they could see increased user engagement. Chainlink VRF offers a transparent and cryptographically enforced RNG solution that can re-establish trust in marketing campaigns by creating a level playing field for all participants.
Selecting Between Possible Event Locations and Details
Popular events garner interest from all over the world, with users often vying to influence event details like bringing its location closer to home. While event organizers are likely to whittle down the choices to a few select locations or details, they can then use randomness to select between the remaining options to ensure there is no bias in choices. For example, a popular music event can switch cities each year, and randomness can be used to select the next location from a list of 5 options. To further engage fans, they can vote to see which 5 options make up the list prior to selection. Event organizers can go even further to include a randomized selection of themes and headline speakers.
Fair Selection and Ordering Processes
Randomness is a key input to fair selection and order processes, particularly when demand exceeds availability or when supply is higher than the pool of interested participants. Projects can use Chainlink VRF to pick the select few users to participate in high-demand events, pick the unlucky few to have to participate in low-demand events, or order participants—all in an entirely auditable manner.
Easily Integrate Verifiable Randomness
Whitelisting Users for IDO Allocations
Initial DEX offerings (IDOs) enable projects to raise funds for project development and distribute tokens to the public using a decentralized exchange. IDOs for popular projects can garner high demand and quickly sell out, making it difficult at times to participate. Launchpads have tried to democratize this process by pooling funds together to participate in IDOs, however, there still isn’t’ always room for all their community members to get an allocation. Thus, randomness can help determine which users receive allocations from specific IDOs.
Multiple projects have integrated Chainlink VRF to power their launchpad, including: Cardence, Cardstarter, MaticLaunch, Poolz, Rainicorn, RoboFi, Seedify.fund, Starter, Synapse Network, TrustPad, Zero Exchange, and ZeroSwap.
“In traditional launchpad distributions, auditability and fairness were simply not present. With Chainlink now a foundational component of the 0.Exchange ecosystem, we can provide users with cryptographic guarantees on the unbiased and ungameable distribution of allocations.”
– Gram Custodian, Head of Zero Exchange
It’s estimated that around 15% of the adult American population is summoned to jury duty each year. Around the world, including in the United States today, jurors are still selected in opaque, manual processes, such as blindfolding a clerk and drawing names from a box. While some jurisdictions use computers, it’s still a nontransparent process that’s difficult to verify whether favoritism or bias occurred—a serious concern since jurors alone can decide the fate of an individual in court.
PAID Network offers a legal toolkit for businesses and individuals to create SMART Agreements that automate business processes. Instead of relying on intermediaries to sign legal agreements, PAID Network uses real-world data to prove certain contract conditions and automate outcomes. However, some contracts end in dispute, so PAID Network implemented an escrow and arbitration system. In order to help mitigate Sybil-attacks, Paid Network plans to use Chainlink VRF to select three jurors from the total group of staked Arbitrators to pass judgment on disputes.
“PAID Network must use a random number generator to select our Arbitrators at random, but it’s been difficult finding the perfect solution. Now with Chainlink VRF, we have an ideal solution built specifically to satisfy the security and transparency requirements of smart contracts.”
– Kyle Chassé, Founder & CEO of PAID Network
Onboarding New DAO Members and Breaking Ties
Decentralized Autonomous Organizations (DAOs) consist of individuals and teams who work together to make critical decisions for an organization or an entity. DAOs have risen in popularity due to their ability to manage dApps in a decentralized and democratized manner. While having a large community is good, sometimes DAOs can better operate with a smaller board of directors to execute day-to-day decisions more efficiently and effectively on behalf of the community.
Part of managing a board of directors involves voting in new members when seats are vacant or up for replacement. Though not the primary means of decision making, fair randomness from Chainlink VRF can be used to break ties or fairly onboard individuals from a list of potential members wanting to join.
Given the wide range of assets in financial markets, it can be difficult to price long-tail or rare assets that don’t have a lot of trading volume or liquidity. Pricing illiquid assets such as NFTs can benefit from industry experts to serve as appraisers. For example, Upshot is a decentralized platform specializing in giving second opinions on NFT appraisals using a decentralized and financial-incentivized group of appraisers. Upshot integrated Chainlink VRF to randomize the selection process of appraisers, helping remove situations like the highest coin holder always being selected or savvy appraisers predicting when their turn is up and manipulating the outcome to their advantage.
Check out Upshot’s interview on Chainlink Live to learn more:
Tax organizations, accounting firms, and other corporations use randomized auditing to ensure recordkeeping processes are accurate. Though these auditing systems are largely automated, they are often opaque, meaning it’s unclear to the party being audited why they were selected over another entity. There have been calls to create a more transparent process where everyone can verify the objectivity and impartiality of the selection process. By using Chainlink VRF as an RNG solution for randomized audits, governments and organizations can prove to their constituents that the process was equally fair to each party.
It’s all too common for people to excitedly wait for their favorite concert or sporting event tickets to be released for sale online, only to find out that all of the tickets have been purchased in seconds. Not only is it estimated that bots generate 40% of all ticketing traffic, but it’s also unclear whether people close to the promoters get backdoor access to high-demand events. A secure and verifiable source of randomness can transform ticketing order queues to democratize access to popular events.
GET Protocol is a blockchain-based events solution platform bringing fairness to the ticketing industry. Instead of releasing tickets in a first-come-first-served manner, GET Protocol is integrating Chainlink VRF to randomize ticket queues based on the pool of participants who signed up to attend beforehand. Through Chainlink VRF, GET Protocol can give everyone an equal opportunity to gain access to their favorite events.
Sampling in Polls and Clinical Trials
Whether conducting public opinion polls, organizing a census, or selecting participants in a clinical trial, sampling is an important part of generating outcomes. For example, the United States Census Bureau conducts scientific sampling from 3.5 million addresses each year. However, bias in sampling can really hinder the objectivity of the samples, and a lack of transparency can put the integrity of the study in question. One way to increase accountability and help prevent sampling fraud is to use Chainlink VRF for the impartial selection of study participants.
Authentication and Security
Authentication and security are important to any online process, especially when a lot of value is at risk. The cryptocurrency market alone is already over 2 trillion dollars. One fundamental aspect of security is unpredictability, as malicious entities cannot attack what they cannot predict easily. Randomness is the root of unpredictability, meaning Chainlink VRF can help users authenticate and secure processes.
Another problem with the ticketing industry is fraud, such as fake tickets, scalping, scamming, and more. In fact, over 12% of Americans who purchase tickets are scammed. In order to mitigate these problems, blockchain-based ticketing platform DigiTix issues each ticket as an NFT, meaning anyone can verify the origin of the ticket on-chain to avoid counterfeits. In addition to using Chainlink Price Feeds for exchange rates, DigiTix also integrated Chainlink VRF to authenticate tickets in a manner that is unpredictable, helping eliminate the ability to reverse engineer ticket authentication.
Sampling in Consensus Mechanisms
Blockchains reach consensus through a decentralized network of nodes all agreeing on the state of new transactions added to the ledger. While increased decentralization can lead to more security, it can also have the tradeoff of reduced efficiency. Hence, why some blockchain consensus mechanisms sample from the total pool of nodes to reach consensus quicker while reducing the ability of miners/validators to predict the ordering. Chainlink VRF can be used as an input for sampling random miners/validators for block production or to randomly select new block leaders in a fair and verifiable manner.
While an extensive set of use cases has been laid out, it’s important to remember that new use cases for Chainlink VRF are being discovered every day. The desire for fairness, security, and transparency are fundamental virtues that make blockchain-based applications stand out in comparison to Web 2.0 alternatives, and Chainlink VRF is an essential building block for developers wanting to realize these ideals via provably fair and tamper-proof randomness.
If you’re a developer and want to quickly get your application connected to Chainlink VRF, visit the developer documentation and join the technical discussion in Discord. If you want to schedule a call to discuss the integration more in-depth, reach out here.