To buy Lightchain AI (LCAI) using ETH that is currently on the Base mainnet, you will need to transfer your ETH to the Ethereum mainnet. Here are the steps to accomplish this:

1. Bridging Your ETH: You can bridge your ETH from the Base mainnet to the Ethereum mainnet. There are various platforms available that facilitate this process. Here's a useful resource to get started: Superchain Bridges - Base Docs, which provides a comprehensive guide on how to bridge assets between the two networks.

2. Using a Bridge: You can use applications like the Base bridge to swap your ETH to the Ethereum mainnet directly. Keep in mind that bridging may involve transaction fees. A helpful link with detailed instructions is available here: Recover tokens from Base Network to Ethereum mainnet.

3. Alternative Methods: If the bridge fees are too high, another option could be sending your ETH to an exchange (like Coinbase), converting it there, and then withdrawing it back to your MetaMask wallet on the Ethereum mainnet.

4. Confirm Your ETH Balance: Once you have bridged your ETH to the Ethereum mainnet, check your MetaMask wallet again to ensure that the ETH is now reflected on the Ethereum mainnet.

5. Purchase LCAI Tokens: Once your ETH is on the Ethereum mainnet, you can follow the previously mentioned steps to buy LCAI tokens.

In summary, since your ETH is on the Base mainnet, you need to bridge it to the Ethereum mainnet before purchasing LCAI. After successfully bridging, you'll be able to use your ETH to complete the transaction.

Sources

Changing base ethereum to main ethereum - RedditHow to Bridge Tokens from ETH Mainnet to Base | PancakeSwapSuperchain Bridges - Base DocsRecover tokens from base Network to Ethereum mainnetHOW TO WITHDRAW ETH FROM BASE TO ETHEREUM MAINNET ...Ethereum (Base) (ETHBASE) to Ethereum (ETH) Simple ExchangeBridge tokens from the BASE network to Ethereum chain (ETH)

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