Confidence:StrongSolidPlausibleTentativeSpeculative

• Sarkhan's Unsealing

  3R

  EnchantmentR

  Both cards trigger when a spell is cast — they fire together.
• Quintorius Kand

  3RW

  Legendary Planeswalker — QuintoriusRW

  Both cards trigger when a spell is cast — they fire together.
• Primeval Bounty

  5G

  EnchantmentG

  Both cards trigger when a spell is cast — they fire together.
• Reanimate

  B

  SorceryB

  Reanimate puts Riku of Many Paths onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Helping Hand

  W

  SorceryW

  Helping Hand puts Riku of Many Paths onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Unearth

  B

  SorceryB

  Unearth puts Riku of Many Paths onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Kasla, the Broken Halo

  3URW

  Legendary Creature — Angel AllyRUW

  Both cards trigger when a spell is cast — they fire together.
• Grave Researcher // Reanimate

  2BB

  Creature — Troll Warlock // SorceryB

  Grave Researcher puts Riku of Many Paths onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Thor, God of Thunder

  3RR

  Legendary Creature — God Warrior HeroR

  Both cards trigger when a spell is cast — they fire together.
• Pink Horror

  3UR

  Creature — Demon HorrorRU

  Both cards trigger when a spell is cast — they fire together.
• Murmuration

  4W

  EnchantmentW

  Both cards produce the same kind of effect (shared token subtype).
• Taigam, Master Opportunist

  1U

  Legendary Creature — Human MonkU

  Both cards trigger when a spell is cast — they fire together.
• Ashling, Flame Dancer

  2RR

  Legendary Creature — Elemental ShamanR

  Both cards trigger when a spell is cast — they fire together.
• Kykar, Zephyr Awakener

  2WU

  Legendary Creature — Bird WizardUW

  Both cards trigger when a spell is cast — they fire together.
• Rage Extractor

  4R/P

  ArtifactR

  Both cards trigger when a spell is cast — they fire together.
• Tor Wauki the Younger

  3BR

  Legendary Creature — Human ArcherBR

  Both cards trigger when a spell is cast — they fire together.
• Sorin of House Markov // Sorin, Ravenous Neonate

  1B

  Legendary Creature — Human Noble // Legendary Planeswalker — SorinBW

  Both cards trigger when a spell is cast — they fire together.
• Harmonic Prodigy

  1R

  Creature — Human WizardR

  Harmonic Prodigy makes Riku of Many Paths's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Summon: Good King Mog XII

  4W

  Enchantment Creature — Saga MoogleW

  Both cards trigger when a spell is cast — they fire together.
• Surtr, Fiery Jötun

  3RR

  Legendary Creature — Giant God WarriorR

  Both cards trigger when a spell is cast — they fire together.
• Scytheclaw Raptor

  2R

  Creature — DinosaurR

  Both cards trigger when a spell is cast — they fire together.
• The Fantastic Four

  RGWU

  Legendary Creature — Human HeroGRUW

  Both cards trigger when a spell is cast — they fire together.
• Loki, God of Lies

  1RR

  Legendary Creature — God Sorcerer VillainR

  Both cards trigger when a spell is cast — they fire together.
• Cemetery Gatekeeper

  1R

  Creature — VampireR

  Both cards trigger when a spell is cast — they fire together.
• Longshot, Rebel Bowman

  3R

  Legendary Creature — Human Rebel AllyR

  Both cards trigger when a spell is cast — they fire together.