MegaWorld Integrates Chainlink VRF To Help Power Randomized In-Game Events

Mega Crypto Polis
3 min readDec 13, 2022

Ever since going live in 2017, the MegaWorld decentralized city-builder, which is one of the first blockchain-powered strategy games with lots of variables and assets, has been taking the player-driven economy approach, leaving no dependency to chance — an outcome of any action in the game has always been dependent solely on players’ decisions and tactics. Until now.

Today, we’re excited to announce that we have 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 power in-game mechanics, including determining avatar traits and qualifications in the citizen breeding process and natural disasters happenings.

In order to help randomize these in-game mechanics, we need 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 MegaWorld 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 citizen breeding process and natural disaster happenings are provably fair and were not tampered with by the oracle, outside entities, or the MegaWorld team.

Moreover, in order to commemorate this integration, Chainlink, among a few other ecosystem projects, will receive an office building in the new metaverse city. These buildings will be unveiled during the new city’s demo.

After the MegaWorld Alpha release planned for 2023, players will be able to visit the Chainlink office building in the MegaWorld metaverse to learn more about its technology and how the platform is critical for Web3 and MegaWorld in particular.

The new reality is already here — welcome to the decentralized city. Take a deep digital breath of freedom.

“It’s clear why Chainlink VRF is the industry standard randomness solution. Being able to leverage a verifiable source of randomness helps us to provide our users with unexpected in-game outcomes in a provably fair manner.” — Alex Li, COO

About Chainlink

Chainlink is the industry-standard Web3 services platform that has enabled trillions of dollars in transaction volume across DeFi, insurance, gaming, NFTs, and other major industries. As the leading decentralized oracle network, Chainlink enables developers to build feature-rich Web3 applications with seamless access to real-world data and off-chain computation across any blockchain and provides global enterprises with 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 MegaWorld

MegaWorld is a player-driven economic metaverse, based on one of the first blockchain-powered strategy games called MegaCryptoPolis, running smoothly since 2017. With multiple blockchains available for players, the game offers an opportunity for players to try their strategic minds in developing a decentralized city with a real economy, along with more than 25,000 passionate players.



Mega Crypto Polis

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