Karn, Legacy Reforged (Retro) [March of the Machine: The Aftermath] Zombie Mongoose while the Iconarch hoists a

while the Iconarch hoists a daemonic icon roaring with flames

but how could that be

where X is the number of descent counters on Descent into Avernus

Set: EX: Power Keepers Type: Psychic Rarity: Holo Rare Retreat cost: Colorless

Then do it again

Karn, Legacy Reforged (Retro) [March of the Machine: The Aftermath] Zombie Mongoose while the Iconarch hoists aSet: 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.