Search your library for a Plains card. If target opponent controls more lands than you, you may search your library for an additional Plains card. Reveal those cards and put them into your hand. Then shuffle your library.
10/4/2004 Counts lands on resolution, not on announcement.
10/4/2004 Because the “search” requires you to find a card with certain characteristics, you don’t have to find the card if you don’t want to.