Oreskos Explorer

When Oreskos Explorer enters, search your library for up to X Plains cards, where X is the number of players who control more lands than you. Reveal those cards, put them into your hand, then shuffle.

The List

Commander Masters

When Oreskos Explorer enters the battlefield, search your library for up to X Plains cards, where X is the number of players who control more lands than you. Reveal those cards, put them into your hand, then shuffle.

Commander 2021

Commander Legends

When Oreskos Explorer enters the battlefield, search your library for up to X Plains cards, where X is the number of players who control more lands than you. Reveal those cards, put them into your hand, then shuffle your library.

Commander Anthology Volume II

If no player controls more lands than you do, you'll still search and shuffle your library, although you can't find any cards.

The value of X is determined as Oreskos Explorer's triggered ability resolves.