Leonin Arbiter

If an effect says "You may search your library . . . If you do, shuffle your library" or "You may search your library . . . then shuffle your library," you can't choose to search, so you won't shuffle.

Wotc — January 01, 2011

If an effect says "Search your library . . . then shuffle your library," you shuffle you libraries even though you can't search.

Wotc — January 01, 2011

Effects that instruct you to reveal or look at cards from the top of you library will still work. Only effects that use the word "search" are affected.

Wotc — January 01, 2011

Since players who haven't paid {2} can't search, they won't be able to find any cards in a library. The effect applies to all players and all libraries. If a spell or ability's effect has other parts that don't depend on searching for or finding cards, they will still work normally.

Wotc — January 01, 2011

Paying {2} to ignore Leonin Arbiter's effect is a special action. Any player may take this special action any time they have priority. It doesn't use the stack and can't be responded to.

Wotc — January 01, 2011

Paying {2} doesn't let a player pick up a library and search it — it just allows them to ignore Leonin Arbiter's effect that turn. That player can search a library only if another spell or ability instructs them to do so.

Wotc — January 01, 2011

If a player pays {2}, that enables only them to ignore Leonin Arbiter's effect that turn. Each other player is still affected by it.

Wotc — January 01, 2011

A player who has paid {2} may search any library when instructed to do so that turn, not just their own library.

Wotc — January 01, 2011

Once a player has paid {2}, they may search libraries that turn as many times as they are instructed to do so.

Wotc — January 01, 2011

If there are multiple Leonin Arbiters on the battlefield, a player must pay {2} for each one before being able to search libraries that turn.

Wotc — January 01, 2011