Karn, the Great Creator (White Border) [Mystery Booster 2] Zombie Noble The attacking player chooses how

The attacking player chooses how each creature blocks each combat

Set: The List Type: Land Rarity: Rare Cathedral of War enters the battlefield tapped

Set: 30th Anniversary Edition Type: Enchantment Rarity: Rare Cost: {1}{B} Black creatures get +1/+1

If each of those creatures could be blocked by all creatures that the other is blocked by

Karn, the Great Creator (White Border) [Mystery Booster 2] Zombie Noble The attacking player chooses howSet: Mystery Booster 2 Type: Legendary Planeswalker Karn Rarity: Rare Cost: {4} 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 mana value. 2: You may reveal an artifact card you own from outside the game or choose a face up artifact card you own in exile. Put that card into your hand.