Skybridge Towers

Late in a long game, most lands are just topdeck insurance: fine when you need them, dead weight when you do not. This one solves its own dead-draw problem by feeding itself into card advantage. Its first job is unremarkable tapland work: it fixes white and blue, pays the enters-tapped tempo tax that untaxed duals avoid, and carries you to your spells on curve. The payoff arrives once your mana is online and this source is no longer earning its keep producing colors. Then it converts a redundant land into a fresh card at a price only surplus mana would ever pay: two generic plus a white and a blue, on top of sacrificing the land. That activation is deliberately steep so it never elbows out your real spells early; it comes online only in the turns where you have mana banked and nothing pressing to point it at. The trade is entry speed (this always arrives tapped, with no condition to sneak past that) for a late-game floor no basic and no fetchland offers. It answers a specific brief: keep every mana source relevant deep into a grind without padding the spell count. And it happens to serve the color pair with the longest history of winning by simply drawing more cards than the opponent, which is exactly the strategy most eager to trade a land for one.