Eclipsed Merrow

Look four deep, take a Merfolk, a Plains, or an Island, and send the rest away: that is a deliberately fenced-in dig, closer to a land-or-lord tutor than a generic card-advantage engine. The narrowness is the point. Whiff on all three valid hits and the four scatter back into your deck, so the ability pays out for a build packed with the exact card types it names rather than a pile of otherwise good cards. What makes the selection matter more than its rate suggests is the cost that funds it: payable entirely from either half of an Azorius manabase, the creature slots in whether your early lands lean white or blue, smoothing the awkward turns where a two-color aggressive tribe stumbles on colored requirements. That flexibility means it can dig for Plains and more Merfolk from a white-heavy hand, or reach for Islands from a blue one, without the manabase ever forcing the choice. The 2/3 body survives most early combat while doing this fixing-and-filtering work, which is what makes it connective tissue: the kind of piece that holds a two-color tribal aggro deck together without asking to be the centerpiece. It is not a payoff so much as the glue that lets the payoffs arrive on curve.