Undercity Sewers

Surveil 1 on arrival is what turns the tempo hit into a decision. The older tapped duals asked you to pay for two-color fixing with a lost turn and nothing back; this one hands you a scry-with-teeth as compensation, letting you look at your next draw and choose whether it stays or feeds the graveyard. That reframes the enters-tapped clause depending on what your deck is building toward. To a deck that only wants to cast spells on curve, this is a slower dual and the surveil is trim. To a deck that treats its own graveyard as a resource (delve, flashback, threshold, reanimation), the setback stops being pure cost, because the surveil is doing work you would otherwise spend a whole card on. The Island Swamp type line quietly widens the pool of fetches and fixing effects that can find it, which matters more the deeper your manabase leans on nonbasic tutoring. It belongs to a cycle of ten across the color pairs, each a tapped dual with surveil, and the calculus never changes across them: you trade a turn of speed for one filtered card, and whether that trade comes free or expensive tracks exactly how much your deck values what ends up in its yard.