Cosi's Trickster

Creature - Merfolk Wizard 1/1, U (1)
Whenever an opponent shuffles his or her library, you may put a +1/+1 counter on Cosi's Trickster.
She watches the chaos created by the Roil, seeking strength in the patterns of anarchy.
Illus. Igor Kieryluk

Gatherer Card Rulings [Nov 2009]

• 10/1/2009: Cosi's Trickster's ability triggers when an opponent shuffles his or her library because that player was instructed to do so by a spell or ability that specifically contains the word "shuffle" in its text or (in the case of a keyword ability) in its rules.
• 10/1/2009: The cascade ability doesn't cause a player to shuffle his or her library, even if that player revealed his or her entire library. The revealed cards are put on the bottom of their owner's library in a random order, but they're not "shuffled."
• 10/1/2009: If an opponent's library is empty or has just a single card in it when a spell or ability instructs that player to shuffle his or her library, Cosi's Trickster's ability will still trigger.

Format Legality	Legal in Vintage, Legacy, Extended, Standard Banned in MTGO Classic
Printings (1/9)	Zendikar (Rare)