Abundance

The replacement effect is the whole game. By converting every draw into a guaranteed land-or-spell, this turns one of Magic's oldest variance problems (flooding into dead lands, or screwing on a hand full of business) into a knob you control on a card-by-card basis. The subtlety is in what it does to your library: each draw, you name a kind and reveal until you hit it, so naming nonland buries every land you pass over on the bottom. That makes it a quiet deck-thinning engine that cleans up the rest of your draws too. The sorting is why it found a second life alongside Sylvan Library, where the pairing lets you dig without paying the life Sylvan Library's draw-three normally costs: Abundance converts those extra peeks into lifeless card selection. The price it asks in return is that the choice is binary and made blind. You commit to a kind before you see anything, so naming nonland once you have run dry of spells just buries the rest of your library and leaves you drawing nothing at all. As a four-mana enchantment that replaces draws you were already getting rather than generating new ones, it is pure long-game smoothing, the sort of card that rewards grinding green decks over tempo ones. Few enchantments of its era have aged into a clearer statement of what the color does best: trading variance for reliable card quality.