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SKALE
Other Chain·SKALE Nebula Gaming Hub · SKALE Europa Hub · SKALE Calypso Hub · SKALE Titan Hub · SKALE appchains · Ethereum

SKALE

01Description

Multichain network of EVM-compatible appchains and shared 'hub' chains (Europa for DeFi, Calypso for NFTs/consumer, Nebula for gaming, Titan for AI/DAOs). SKALE chains charge zero gas to end users — fees are abstracted via sFUEL (a non-tradeable gas token issued by faucets/distributors) — making it a popular L2/L3 choice for free-to-play Web3 games and NFT mints.

02Best for
  • 01zero-gas-for-players Web3 games (Nebula Hub)
  • 02free-mint NFT drops (Calypso Hub)
  • 03studio-owned appchains with EVM tooling
  • 04high-throughput in-game txs with Solidity contracts
  • 05DeFi/RWA dApps wanting zero player gas (Europa Hub)
03Install
  • pnpm add viem wagmi @skalenetwork/ima-js
04Environment variables
VariableScopeDescription
NEXT_PUBLIC_SKALE_NEBULA_RPC_URLClientSKALE Nebula Hub RPC URL (e.g. https://mainnet.skalenodes.com/v1/green-giddy-denebola).
SKALE_SFUEL_DISTRIBUTOR_KEYServerServer-side key for an sFUEL distributor wallet that drips gas to new players.
05Prompt snippet
Configure viem with the target SKALE chain (e.g. Nebula Gaming Hub, chainId 1482601649) and standard EVM RPC — Solidity contracts deploy unchanged with Foundry/Hardhat. Because SKALE chains have zero base gas price, players still need a tiny sFUEL balance to submit txs; integrate the SKALE sFUEL Station (`https://sfuel.skale.network`) or run your own distributor that calls `eth_sendTransaction` to drip 0.000001 sFUEL to new wallets on first interaction. Bridge ETH and ERC-20s in/out of SKALE via the Interchain Messaging Agent (`@skalenetwork/ima-js`) which connects each SKALE chain to Ethereum L1. ChainSafe's `web3.unity` SDK supports SKALE Nebula natively for Unity games.
06Gotchas
  • Zero gas only means zero protocol fee — players still need a non-zero sFUEL balance to send any tx, and sFUEL is non-tradeable; an empty sFUEL wallet silently rejects txs with cryptic 'insufficient funds' errors. Always integrate an sFUEL distributor on first login.
  • SKALE chains are EVM-compatible but each runs as a separate validator subset — chainIds, RPCs, and bridge endpoints differ per hub/appchain. There is no single 'SKALE mainnet'; use the official portal (portal.skale.space/chains) to resolve chains.
  • Bridging assets between SKALE and Ethereum L1 uses the IMA bridge with a multi-step deposit/withdraw flow (approve -> deposit on L1 -> claim on SKALE, and reverse) — withdrawals can take 30+ minutes and require a transaction on each side.
  • Each SKALE chain has its own file storage and on-chain RNG features that are non-standard EVM precompiles — code that uses them is not portable to other EVM chains.
  • Gas-token quirk: sFUEL has no fiat value and cannot be acquired on exchanges; if your distributor wallet runs dry the entire game halts for new players. Monitor distributor balance and refill from the team's reserve.
  • Peer-to-peer NFT transfers on Calypso are free for sender, but secondary marketplaces that charge fees in ETH/USDC require the buyer to bridge stablecoins in first — surface that bridge step in onboarding.
07Alternatives