Cosi's Trickster
From Zendikar set
Cosi's Trickster
Creature — Merfolk Wizard
1/1
Whenever an opponent shuffles their library, you may put a +1/+1 counter on this creature.
Rulings
- Cosi’s Trickster’s ability triggers when an opponent shuffles their 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.
- The cascade ability doesn’t cause a player to shuffle their library, even if that player revealed their entire library. The revealed cards are put on the bottom of their owner’s library in a random order, but they’re not “shuffled.”
- 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 their library, Cosi’s Trickster’s ability will still trigger.
