Karn, Legacy Reforged (Extended Art) [March of the Machine: The Aftermath]Set: 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.

Set: Dungeons & Dragons: Adventures in the Forgotten Realms Type: Creature — Dragon Rarity: Rare Cost: {3}{R}{W} Flying

−8: You get an emblem with “Whenever you cast a red instant or sorcery spell

Whenever three or more creatures you control with flying attack

Set: Mirrodin Besieged Type: Creature — Phyrexian Horror Rarity: Rare Cost: {2}{B}{B} Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters

({U/P} can be paid with either {U} or {2} life

Set: Rise of the Eldrazi Type: Enchantment Rarity: Rare Cost: {2}{W}{W} Whenever one or more creatures attack

where X is the number of verse counters on Rumbling Crescendo

Set: Return to Ravnica Type: Creature — Demon Rarity: Rare Cost: {2}{B}{B} Flying

Set: Ikoria: Lair of Behemoths Prerelease Promos Type: Legendary Creature — Cat Nightmare Rarity: Rare Cost: {1}{W/B}{W/B} Companion — Each permanent card in your starting deck has mana value 2 or less

Set: Fourth Edition (Foreign Black Border) Type: Creature — Merfolk Rarity: Rare Cost: {U}{U} Other Merfolk get +1/+1 and have islandwalk

What are they going to do

Set: Mirage Type: Enchantment Rarity: Rare Cost: {X}{W}{W} Soul Echo enters the battlefield with X echo counters on it