It seems there might be a misunderstanding or an error in your request. As of my last update in January 2022, there was no widely recognized "Mantle DAO" that had deployed a liquid staking protocol on the Ethereum mainnet. The information you provided might be related to developments or announcements that occurred after my last update.

However, the concept of liquid staking involves converting staked assets into tradable tokens, enabling users to earn staking rewards while retaining liquidity to trade or use these assets in DeFi applications.

If there have been recent developments in the crypto space regarding Mantle DAO and a liquid staking protocol on Ethereum, I recommend checking the latest news sources, official announcements, or cryptocurrency forums for the most accurate and up-to-date information.