Confidence:StrongSolidPlausibleTentativeSpeculative

• Traveling Chocobo

  2G

  Creature — BirdG

  Traveling Chocobo makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Reanimate

  B

  SorceryB

  Reanimate puts Avenger of Zendikar 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 Avenger of Zendikar onto the battlefield from a graveyard without casting it, so its mana cost is never paid.
• Elesh Norn, Mother of Machines

  4W

  Legendary Creature — Phyrexian PraetorW

  Elesh Norn, Mother of Machines makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Virtue of Knowledge // Vantress Visions

  4U1U

  Enchantment // Instant — AdventureU

  Virtue of Knowledge makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Starfield Vocalist

  3U

  Creature — Human BardU

  Starfield Vocalist makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Mirrorhall Mimic // Ghastly Mimicry

  3U

  Creature — Spirit // Enchantment — AuraU

  One-shot copy enabler: a card enters as a copy of another (Phantasmal Image, Body Double, Phyrexian Metamorph), firing the partner's substantive ETB once. Not a repeating chain — fires once on entry — but valuable when the partner's ETB is combo-grade (graveyard reanimator, mana doubler, etc.).
• Insidious Roots

  BG

  EnchantmentBG

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

  4GG

  Creature — ElementalG

  Ancient Greenwarden makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Yarok, the Desecrated

  2BGU

  Legendary Creature — Elemental HorrorBGU

  Yarok, the Desecrated makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Nissa, Voice of Zendikar

  1GG

  Legendary Planeswalker — NissaG

  Both cards produce the same kind of effect (shared token subtype).
• Grismold, the Dreadsower

  1BG

  Legendary Creature — Troll ShamanBG

  Both cards produce the same kind of effect (shared token subtype).
• Ezri Dax, Newly Joined

  1W

  Legendary Creature — Trill AdvisorW

  One-shot copy enabler: a card enters as a copy of another (Phantasmal Image, Body Double, Phyrexian Metamorph), firing the partner's substantive ETB once. Not a repeating chain — fires once on entry — but valuable when the partner's ETB is combo-grade (graveyard reanimator, mana doubler, etc.).
• Vengeful Regrowth

  4GG

  SorceryG

  Both cards produce the same kind of effect (shared token subtype).
• Yuma, Proud Protector

  5RGW

  Legendary Creature — Human RangerGRW

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

  2R

  ArtifactR

  One-shot copy enabler: a card enters as a copy of another (Phantasmal Image, Body Double, Phyrexian Metamorph), firing the partner's substantive ETB once. Not a repeating chain — fires once on entry — but valuable when the partner's ETB is combo-grade (graveyard reanimator, mana doubler, etc.).
• Roaming Throne

  4

  Artifact Creature — GolemC

  Roaming Throne makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Callidus Assassin

  4UB

  Creature — Human Shapeshifter AssassinBU

  One-shot copy enabler: a card enters as a copy of another (Phantasmal Image, Body Double, Phyrexian Metamorph), firing the partner's substantive ETB once. Not a repeating chain — fires once on entry — but valuable when the partner's ETB is combo-grade (graveyard reanimator, mana doubler, etc.).
• Rionya, Fire Dancer

  3RR

  Legendary Creature — Human WizardR

  Copy engine: one card makes copies of a creature — once a turn, or once for each time you pay its cost — and each copy pays off: the creature's enter-the-battlefield effect fires again, or the hasty copy uses its tap ability. Real, repeatable value — every copy has its turn or its price, so it never goes infinite on its own.
• Twinflame Travelers

  2UR

  Creature — Elemental SorcererRU

  Twinflame Travelers makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Deceptive Frostkite

  UU

  Creature — DragonU

  One-shot copy enabler: a card enters as a copy of another (Phantasmal Image, Body Double, Phyrexian Metamorph), firing the partner's substantive ETB once. Not a repeating chain — fires once on entry — but valuable when the partner's ETB is combo-grade (graveyard reanimator, mana doubler, etc.).
• Mirror Room // Fractured Realm

  2U5UU

  Enchantment — Room // Enchantment — RoomU

  Mirror Room makes Avenger of Zendikar's triggered ability trigger an additional time — each time it fires, you get it twice. Value, not a loop.
• Sakashima's Protege

  4UU

  Creature — ShapeshifterU

  One-shot copy enabler: a card enters as a copy of another (Phantasmal Image, Body Double, Phyrexian Metamorph), firing the partner's substantive ETB once. Not a repeating chain — fires once on entry — but valuable when the partner's ETB is combo-grade (graveyard reanimator, mana doubler, etc.).
• Helm of the Host

  4

  Legendary Artifact — EquipmentC

  Copy engine: one card makes copies of a creature — once a turn, or once for each time you pay its cost — and each copy pays off: the creature's enter-the-battlefield effect fires again, or the hasty copy uses its tap ability. Real, repeatable value — every copy has its turn or its price, so it never goes infinite on its own.
• Metamorphic Alteration

  1U

  Enchantment — AuraU

  One-shot copy enabler: a card enters as a copy of another (Phantasmal Image, Body Double, Phyrexian Metamorph), firing the partner's substantive ETB once. Not a repeating chain — fires once on entry — but valuable when the partner's ETB is combo-grade (graveyard reanimator, mana doubler, etc.).