Oracle

Legendary Planeswalker - Karn 

Activated abilities of artifacts your opponents control can't be activated.
+1: Until your next turn, up to one target noncreature artifact becomes an artifact creature with power and toughness each equal to its converted mana cost.
-2: You may choose an artifact card you own from outside the game or in exile, reveal that card, and put it into your hand.

Tournooi-info

Legal in: Legacy, Modern, Commander
Restricted in: Vintage

Officiele rulings

5/3/2019
Activated abilities contain a colon. They’re generally written “[Cost]: [Effect].” Some keyword abilities are activated abilities and will have colons in their reminder text, such as equip. Triggered abilities (starting with “when,” “whenever,” or “at”) are unaffected by Karn.

5/3/2019
Karn’s first ability affects only artifacts on the battlefield. Activated abilities that work in other zones can still be activated.

5/3/2019
A noncreature permanent that turns into a creature can attack, and its T abilities can be activated, only if its controller has continuously controlled that permanent since the beginning of their most recent turn. It doesn’t matter how long the permanent has been a creature.

5/3/2019
If a permanent has X in its mana cost, X is considered to be 0.

5/3/2019
Karn’s last ability can’t get a face-down card in exile, even if you know it’s an artifact card.

5/3/2019
In a casual game, a card you choose from outside the game comes from your personal collection. In a tournament event, a card you choose from outside the game must come from your sideboard. You may look at your sideboard at any time.

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