Seasinger is a uncommon Creature — Merfolk card from Fifth Edition (5ED), collector number 121. Current market price: $0.44, TCGplayer market prices via Scryfall.
When you control no Islands, sacrifice this creature. You may choose not to untap this creature during your untap step. {T}: Gain control of target creature whose controller controls an Island for as long as you control this creature and this creature remains tapped.