Other Chain·Xai · Xai Sepolia (testnet) · Arbitrum One
Xai
Gaming-focused Arbitrum Orbit L3 settling to Arbitrum One via AnyTrust DA. Xai is co-developed with Offchain Labs (a rare 'managed' Orbit chain), uses XAI as the gas token, and secures liveness via a network of Sentry Nodes that respond to Attention Challenges from a Referee contract. SDKs target Unity and Unreal so studios can deploy EVM games with elevated gas/contract limits and cheap transactions.
- 01AAA / mid-core Web3 games on an EVM-compatible chain
- 02Arbitrum Orbit deployments that need tight Offchain Labs support
- 03studios that want Unity/Unreal Web3 SDKs out of the box
- 04high-throughput in-game txs with low fees
- 05bridging assets between Xai and Arbitrum One
- pnpm add viem wagmi
| Variable | Scope | Description |
|---|---|---|
| NEXT_PUBLIC_XAI_RPC_URL | Client | Xai mainnet RPC URL (default https://xai-chain.net/rpc, chainId 660279). |
| NEXT_PUBLIC_XAI_TESTNET_RPC_URL | Client | Xai Sepolia testnet RPC URL (https://testnet-v2.xai-chain.net/rpc). |
Treat Xai as an EVM L3 with chainId 660279 (mainnet) / 37714555429 (Xai Sepolia). Configure viem with `defineChain({ id: 660279, name: 'Xai', nativeCurrency: { symbol: 'XAI', decimals: 18 }, rpcUrls: { default: { http: ['https://xai-chain.net/rpc'] } } })` and reuse standard wagmi/viem flows. Bridge XAI/ETH/ERC-20s to and from Arbitrum One via the official Xai Bridge (an Orbit canonical bridge with multi-hour withdrawal windows). For game clients, use the ChainSafe web3.unity SDK or another Unity/Unreal Web3 SDK — Xai exposes no proprietary engine plugin, just standard EVM JSON-RPC. Sentry Node operators secure liveness via the Referee contract; dApps don't interact with sentries directly.
- ⚑Native gas token is XAI, not ETH — wallets and faucets that default to ETH balance checks will look 'empty' even when the user has gas; the Unity/Unreal SDK must request XAI for gas, not ETH.
- ⚑Xai uses AnyTrust DA (a Data Availability Committee), not full Ethereum DA — withdrawals to Arbitrum One/Ethereum L1 follow Orbit's challenge window (~7 days from Arbitrum, plus L1 finality), so design game economies to tolerate week-long bridge exits.
- ⚑The Sentry Node + Referee model means liveness depends on a permissioned set of license-key holders; an outage in the sentry network can halt the chain — do not assume censorship resistance equivalent to Arbitrum One.
- ⚑Asset bridging is custodial-style via the Orbit canonical bridge contracts — peer-to-peer trades on Xai are cheap, but cross-chain settlement back to Arbitrum/L1 is slow and can be paused by Xai/Offchain Labs in incidents.
- ⚑Block gas limits and contract size limits are higher than Arbitrum One on purpose; verify your tooling (forge/hardhat) doesn't pin to default Arbitrum limits or you'll get unexpected reverts.
- ⚑Two testnets exist (the original Xai Goerli and Xai Sepolia / Testnet v2) — only Xai Sepolia is current; older RPC URLs and chainIds in stale tutorials will silently send tx to a dead network.