Inkfathom Divers is a common Creature — Merfolk Soldier card from The List (PLST), collector number DDT-8. Current market price: $0.14, TCGplayer market prices via Scryfall.
Islandwalk (This creature can't be blocked as long as defending player controls an Island.) When this creature enters, look at the top four cards of your library, then put them back in any order.