Confidence:StrongSolidPlausibleTentativeSpeculative

• Zaxara, the Exemplary

  1BGU

  Legendary Creature — Nightmare HydraBGU

  Both cards produce the same kind of effect (shared token subtype).
• Polukranos Reborn // Polukranos, Engine of Ruin

  GGG

  Legendary Creature — Hydra // Legendary Creature — Phyrexian HydraGW

  Both cards produce the same kind of effect (shared token subtype).
• Reanimate

  B

  SorceryB

  Reanimate puts Hydra Broodmaster 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 Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Sefris of the Hidden Ways

  WUB

  Legendary Creature — Human WizardBUW

  Sefris of the Hidden Ways puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Recurring Nightmare

  2B

  EnchantmentB

  Recurring Nightmare puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Priest of Fell Rites

  WB

  Creature — Human WarlockBW

  Priest of Fell Rites puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Animate Dead

  1B

  Enchantment — AuraB

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

  1B

  SorceryB

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

  G1B

  Sorcery // SorceryBG

  Life puts Hydra Broodmaster 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 Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Victimize

  2B

  SorceryB

  Victimize puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Persist

  1B

  SorceryB

  Persist puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Grakmaw, Skyclave Ravager

  1BG

  Legendary Creature — Hydra HorrorBG

  Both cards produce the same kind of effect (shared token subtype).
• Soul Exchange

  BB

  SorceryB

  Soul Exchange puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Ascent of the Worthy

  1WB

  Enchantment — SagaBW

  Ascent of the Worthy puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Necromancy

  2B

  EnchantmentB

  Necromancy puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Roaming Throne

  4

  Artifact Creature — GolemC

  Roaming Throne makes Hydra Broodmaster's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Mirror Room // Fractured Realm

  2U5UU

  Enchantment — Room // Enchantment — RoomU

  Mirror Room makes Hydra Broodmaster's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Karai, Future of the Foot

  1WB

  Legendary Creature — Human NinjaBW

  Karai, Future of the Foot puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Honored Hydra

  5G

  Creature — Snake HydraG

  Both cards produce the same kind of effect (shared token subtype).
• One Last Job

  2W

  SorceryW

  One Last Job puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Rat King, Verminister

  1B

  Legendary Creature — Rat AvatarB

  Rat King, Verminister puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• The Falcon, Airship Restored

  2B

  Legendary Artifact — VehicleB

  The Falcon, Airship Restored puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Reincarnation

  1GG

  InstantG

  Reincarnation puts Hydra Broodmaster onto the battlefield from a graveyard without casting it, so its mana cost is never paid.