Cosmic eel is a valuable catch in the Harvest Moon game. This fish can be found in the river during stormy days and at night. If you manage to catch a Cosmic heart fish, you can sell it for a decent sum of money. In addition to its price, it is also in demand by fishing enthusiasts for its exquisite appearance. So, grab your tackle box and head to the creek side to try your luck at hooking this Cosmic heart fish. Happy fishing!