Merchant of Secrets

Strip the body away and you have an Elvish Visionary in blue: a creature that replaces itself with a card the moment it lands. The 1/1 barely registers as a combatant. What you are paying for is a draw spell stapled to a permanent, and the permanent half is where the value lives. A naked card-draw spell is gone once it resolves; this one leaves a creature behind, which means it can be returned to hand, blinked, reanimated, or bounced to do the whole thing again. That recursion loop is the entire reason the card outlives its terrible rate. On its face, paying a full extra mana over a two-mana cantrip for a body that trades down to almost anything is a bad deal. The trade becomes good only when you stop treating the draw as the payoff and start treating the enters-the-battlefield trigger as a renewable resource: a sacrifice-and-recur engine, a flicker target, a body whose death is the point because it draws again on the way back. Blue has accumulated stronger versions of this template over the years, but the structural idea (a flimsy Wizard whose only job is to convert mana into a card every time it touches the battlefield) is durable enough that the cheap, dependable original keeps finding work in builds that care less about the rate than about how many times they can replay the trigger.