Karn, Silver Golem (Kai Budde) [World Championship Decks 1999] Fusion Strike or blue creature

or blue creature

Set: Portal Second Age Type: Sorcery Rarity: Rare Cost: {4}{R}{R} Each player sacrifices four lands

the ATK/DEF of those changed monsters become 0

"Late Thaw"

Set: Aether Revolt Type: Legendary Artifact Rarity: Mythic Cost: {5} Whenever you cast a spell

Karn, Silver Golem (Kai Budde) [World Championship Decks 1999] Fusion Strike or blue creatureSet: World Championship Decks 1999 Type: Legendary Artifact Creature Golem Rarity: Rare Cost: {5} Whenever Karn, Silver Golem blocks or becomes blocked, it gets 4 +4 until end of turn. {1}: Target noncreature artifact becomes an artifact creature with power and toughness each equal to its converted mana cost until end of turn.