Treasure Mage

A tutor with a floor, which is the whole reason it endures. Searching your library is cheap in deckbuilding terms but expensive in card economy: most tutors hand you a card and leave a 2/2-shaped hole where a body should be. This one closes the gap by stapling the search to a creature, so the artifact-ramp shells that want to cheat out a six-mana-plus payoff get to advance their board and assemble their gameplan in the same play. The mana-value-six floor is the constraint doing the real work: it locks the tutor out of the cheap utility artifacts that would make it a generically efficient blue card, and points it squarely at the top end (the Wurmcoil Engines, the colossal artifact finishers a dedicated build is straining toward). That restriction is also what gives the tutor its meaning; you have to actually want the expensive thing for it to count. Pair it with Trinket Mage and you get the two ends of the curve, one Wizard fetching the cheap setup and the other the haymaker, a clean two-card scaffold for any artifact deck that wants both halves.