The article delves into a thorough analysis of the success factors and potential risks of the Ethena stablecoin protocol. Ethena achieves tokenization of arbitrage trading against ETH's Delta neutrality through the issuance of the stablecoin USD, offering attractive annualized returns. Its success lies in providing short-selling liquidity for perpetual contract markets on centralized exchanges, reducing funding rates, and enhancing market vitality. However, the article points out the risk of a death spiral caused by a widening basis, which could amplify losses during market panics and runs, triggering broader redemption waves. While negative rate environments are uncommon, basis issues may render Ethena vulnerable to runs.