Complete Guide: Implementing Magic Eden Multichain Wallet Integration for Polygon Transactions

Executive Summary

This post chronicles the complete journey of integrating Magic Eden's multichain wallet functionality for executing NFT burn transactions on the Polygon network. The integration required understanding Magic Eden's novel wallet architecture, correctly distinguishing between their multiChain and ethereum providers, and resolving critical differences from traditional wallet providers like MetaMask or Coinbase Wallet.

Final Outcome: Successfully enabled Polygon transactions using Magic Eden Wallet, reducing gas costs from ~$0.20 on Ethereum to <$0.01 on Polygon.

Initial Problem Statement

Issue: While testing Magic Eden Wallet for NFT burns on Polygon, the wallet was defaulting to Ethereum mainnet. It prompted users to pay ETH gas fees (~0.0001 ETH), defeating the cost-saving purpose of Polygon.

Key Symptoms:

  • Magic Eden wallet UI showed "Ethereum Chain"

  • Transactions posted to Etherscan (not Polygonscan)

  • Backend reward logic failed to detect burns due to wrong network

Key Resources & Documentation

🔗 Sandbox Repository: https://github.com/Tcadle434/me-wallet-sandbox

Files of Interest:

  • src/components/App.tsx – Chain selection implementation

  • src/components/MultichainMethods.tsx – Multichain connection/signing

  • src/components/EvmMethods.tsx – EVM transaction patterns

  • src/utils/multichain/signMessage.ts – Multichain signing utility

  • src/utils/evm/sendTransaction.ts – Transaction submission utility

Key Learnings:

  • multiChain handles address management and signing, not transactions

  • Polygon transactions must use window.magicEden.ethereum

  • Chain switching is supported via wallet_switchEthereumChain

Magic Eden Wallet Architecture

window.magicEden = {
  bitcoin: {...},        // BTC
  ethereum: {...},       // ETH, Polygon, Base (EVM)
  solana: {...},         // Solana
  multiChain: {...}      // Address management, cross-chain features
};

Architecture Summary:

  • multiChain: Address abstraction layer

  • ethereum: Used for all EVM transactions (ETH, Polygon, Base)

  • multiChain is not a transaction provider

Journey of Challenges & Solutions

🚫 Challenge 1: Stack Overflow Error

Issue: Passing multiChain into BrowserProvider() caused infinite recursion.

provider = new BrowserProvider(window.magicEden.multiChain); // ❌

Fix: Use multiChain only to retrieve the wallet address. Use ethereum for all txs.

🚫 Challenge 2: Address Format

Issue: Magic Eden's multiChain returns Ethereum addresses as arrays.

['0x4796574fc34E02A98972dDFd073709FDcbBd8F73']

Fix: Extract first array element manually.

const ethAddresses = multichainResponse.addresses.ethereum;
const userAddress = Array.isArray(ethAddresses) ? ethAddresses[0] : ethAddresses;

🚫 Challenge 3: Wrong Transaction Provider

Issue: Tried using multiChain.sendTransaction() or .request() (doesn’t exist)
Fix:

  • Extract address from multiChain

  • Use window.magicEden.ethereum as transaction provider

🚫 Challenge 4: Chain Switching Misunderstanding

Assumed: Magic Eden didn’t support chain switching
Fix: Found working wallet_switchEthereumChain call in EvmMethods.tsx

await ethereumProvider.request({
  method: 'wallet_switchEthereumChain',
  params: [{ chainId: '0x89' }], // Polygon
});

✅ Final Working Implementation

1. Address Extraction

const multiChain = window.magicEden?.multiChain;
if (multiChain && multiChain.isConnected) {
  const multichainResponse = multiChain.currentMultiChainResponse;
  const ethAddresses = multichainResponse.addresses.ethereum;
  userAddress = Array.isArray(ethAddresses) ? ethAddresses[0] : ethAddresses;

  provider = new BrowserProvider(window.magicEden.ethereum);
  signer = await provider.getSigner();
}

2. Network Switching

await window.magicEden.ethereum.request({
  method: 'wallet_switchEthereumChain',
  params: [{ chainId: '0x89' }],
});

3. EVM Transaction

const nftContract = new Contract(
  contractAddress,
  ['function safeTransferFrom(address from, address to, uint256 tokenId)'],
  signer
);

await nftContract.safeTransferFrom(userAddress, burnAddress, BigInt(tokenId), {
  gasLimit: 300_000,
  chainId: 137,
});

⚠️ Gotchas & Lessons Learned

  1. Provider Roles Are Distinct

    • multiChain is not a transaction provider

    • ethereum handles all EVM chains (ETH, Polygon, Base)

  2. Array-Based Address Responses

    • Always extract with Array.isArray(addresses) ? addresses[0] : addresses

  3. Chain Switching Is Supported

    • Use wallet_switchEthereumChain for Polygon (chainId: 0x89)

  4. Follow the Sandbox Examples

    • Avoid assumptions; reference real-world implementations

✅ Implementation Verified

Success Criteria:

  • ✅ Wallet prompts for Polygon switch

  • ✅ Transactions appear on Polygonscan

  • ✅ Gas costs are ~$0.005 POL

  • ✅ Backend correctly detects Polygon burns

  • ✅ NFT upgrade rewards issued

Resolved Errors:

  • ❌ Maximum call stack size exceeded → Fixed by using correct provider

  • ❌ toLowerCase is not a function → Fixed by array extraction

  • ❌ sendTransaction is not a function → Resolved by not misusing multiChain

Recommended Dev Approach

  1. Start with Magic Eden's sandbox repo

  2. Separate provider responsibilities:

    • multiChain: For address retrieval only

    • ethereum: For all EVM-compatible txs

  3. Always switch network before tx execution

  4. Follow standard ethers.js transaction patterns

  5. Verify on correct network explorer (Polygonscan, not Etherscan)

Technical Specs Summary

  • Polygon chainId: 0x89 (hex) / 137 (dec)

  • ME Wallet providers: window.magicEden.ethereum, multiChain

  • Supported EVM chains: Ethereum (0x1), Polygon (0x89), Base (0x2105)

  • Tools Used:

    • Magic Eden sandbox

    • ethers.js v6

    • React app

    • Polygonscan

Conclusion

Magic Eden Wallet’s multichain architecture requires a nuanced approach: use multiChain for address resolution, and ethereum for EVM transactions. Chain switching is fully supported and must be explicitly invoked. Developers who rely on real-world code (not assumptions) and correctly extract array-based addresses will find integration straightforward.

This guide demystifies Magic Eden’s multichain setup and enables efficient NFT workflows on Polygon. With these tools, developers can offer seamless multichain support with low gas costs and reliable UX.