Eclipsed Merrow is a uncommon Creature — Merfolk Scout card from Lorwyn Eclipsed (ECL), collector number 221. Current market price: $0.16 (foil $0.29), TCGplayer market prices via Scryfall.
When this creature enters, look at the top four cards of your library. You may reveal a Merfolk, Plains, or Island card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.