Serenity, a leading US stock trading signal provider, has made short-term investments in Ethereum (ETH) and Bitcoin (BTC) spot ETFs, according to on-chain analyst Ai Yi. The trades involved purchasing ETHA at $1,750 and IBIT at $62,000. These ETFs, launched by BlackRock, are not intended for long-term holding by Serenity, indicating a strategy focused on immediate gains rather than sustained investment.