Confidence:StrongSolidPlausibleTentativeSpeculative

• Reanimate

  B

  SorceryB

  Reanimate puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Grave Researcher // Reanimate

  2BB

  Creature — Troll Warlock // SorceryB

  Grave Researcher puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Mikey & Leo, Chaos & Order

  G/WG/W

  Legendary Creature — Mutant Ninja TurtleGW

  Both cards trigger when a counter is placed — they fire together.
• Priest of Fell Rites

  WB

  Creature — Human WarlockBW

  Priest of Fell Rites puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Hollowmurk Siege

  BG

  EnchantmentBG

  Both cards trigger when a counter is placed — they fire together.
• Animate Dead

  1B

  Enchantment — AuraB

  Animate Dead puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Exhume

  1B

  SorceryB

  Exhume puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Life // Death

  G1B

  Sorcery // SorceryBG

  Life puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Dance of the Dead

  1B

  Enchantment — AuraB

  Dance of the Dead puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Soul Exchange

  BB

  SorceryB

  Soul Exchange puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Omarthis, Ghostfire Initiate

  XX

  Legendary Creature — Spirit SnakeC

  Both cards trigger when a counter is placed — they fire together.
• Earth Kingdom General

  3G

  Creature — Human Soldier AllyG

  Both cards trigger when a counter is placed — they fire together.
• Annie Joins Up

  1RGW

  Legendary EnchantmentGRW

  Annie Joins Up makes Chekov and McCoy's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Terrasymbiosis

  2G

  EnchantmentG

  Both cards trigger when a counter is placed — they fire together.
• Botanical Brawler

  GW

  Creature — Elemental WarriorGW

  Both cards trigger when a counter is placed — they fire together.
• Roaming Throne

  4

  Artifact Creature — GolemC

  Roaming Throne makes Chekov and McCoy's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Stocking the Pantry

  G

  EnchantmentG

  Both cards trigger when a counter is placed — they fire together.
• Kros, Defense Contractor

  1GWU

  Legendary Creature — Cat AdvisorGUW

  Both cards trigger when a counter is placed — they fire together.
• Mirror Room // Fractured Realm

  2U5UU

  Enchantment — Room // Enchantment — RoomU

  Mirror Room makes Chekov and McCoy's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Casey Jones, Back Alley Brute

  3R

  Legendary Creature — Human BerserkerR

  Both cards trigger when a counter is placed — they fire together.
• Knight of Wundagore

  1G

  Creature — Cat Knight VillainG

  Both cards trigger when a counter is placed — they fire together.
• Ant-Man, Colony Commander

  1GU

  Legendary Creature — Human Rogue HeroGU

  Both cards trigger when a counter is placed — they fire together.
• Shalai and Hallar

  1RGW

  Legendary Creature — Angel ElfGRW

  Both cards trigger when a counter is placed — they fire together.
• Rat King, Verminister

  1B

  Legendary Creature — Rat AvatarB

  Rat King, Verminister puts Chekov and McCoy onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Moss-Pit Skeleton

  BG

  Creature — Plant SkeletonBG

  Both cards trigger when a counter is placed — they fire together.