Merrow Harbinger
b47af11c-1090-4f0a-8eea-64a3b639e535
$0.50 CND
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
When Merrow Harbinger enters the battlefield, you may search your library for a Merfolk card, reveal it, then shuffle your library and put that card on top of it.