Karn, Legacy Reforged [March of the Machine: The Aftermath] Modern you may exile a green

you may exile a green card from your hand rather than pay this spell's mana cost

For each player

Set: Alpha Edition Type: Artifact Rarity: Rare Cost: {4} Red creatures get +1/+1

sacrifice Sea Serpent

Karn, Legacy Reforged [March of the Machine: The Aftermath] Modern you may exile a greenSet: March of the Machine: The Aftermath Type: Legendary Artifact Creature Golem Rarity: Mythic Cost: {5} Karn, Legacy Reforged's power and toughness are each equal to the greatest mana value among artifacts you control. At the beginning of your upkeep, add {C} for each artifact you control. This mana can't be spent to cast nonartifact spells. Until end of turn, you don't lose this mana as steps and phases end.