
Enchantment
At the beginning of your upkeep, if an opponent controls more lands than you, you may search your library for up to three basic land cards, reveal them, put them into your hand, then shuffle.

White instant that fetches basic lands when opponents have more, same catch-up ramp role.

White sorcery fetching three plains when behind on lands, near-identical effect.

White creature tutoring any land when behind on lands.

White-tuned artifact card advantage engine pairing with basic-heavy decks.

White enchantment generating treasure ramp, similar upkeep value engine.

Classic Land Tax combo to filter excess lands into fresh cards.

Recycles fetched basics back into library, enabling repeated draws with Land Tax.

White creature fetching a plains when opponents control more lands.
You shuffle your library if you search, even if you don't put any basic land cards into your hand.
This ability has an "intervening 'if' clause." That means (1) the ability won't trigger at all unless any one of your opponents controls more lands than you, and (2) the ability will do nothing if you control at least as many lands as each of your opponents by the time it resolves.
You can fetch any of the "Snow-Covered" lands, since they all also have the supertype basic.