Rofellos, Llanowar Emissary

The thing that has always made this Elf dangerous is the asymmetry between what it costs and what it produces. Llanowar Elves and its kin add a single mana, a fixed exchange that ramps you one step ahead. This one scales: in a deck built to flood the board with Forests, the second-turn payoff can already eclipse anything else available at the price, and the curve only steepens from there. That scaling is also the design's only restraint. It counts Forests, not lands, so the moment you splash off-color basics or lean on nonbasic fixing the engine sputters; the reward is bolted to a commitment to mono-green's least flexible manabase. The friction is real, but in the decks willing to pay it, the acceleration crosses the line from ramp into the kind of explosive starts that read as broken. Wizards understood this quickly. Designers have since been notably reluctant to print mana producers that scale off permanent count without a hard cap or a color tax, and the card that did it earliest and cleanest remains a touchstone for how steep a two-mana dork is allowed to get. The 2/1 body is almost beside the point: nobody runs this for combat. It is a mana engine wearing a creature's clothes, and the legend rule is doing quiet balancing work, ensuring you only ever get one going at a time.