Cards that copy spells
Copy your own spell for value, or copy theirs and turn it around. Includes the storm payoffs that copy everything you cast.
Edit it and search again — it reads plain English, so cards that copy spells under 3 mana works too.

Flusterstorm InstantCounter target instant or sorcery spell unless its controller pays {1}. Storm (When you cast this spell, copy it for each spell ca$8.59

Sevinne's Reclamation SorceryReturn target permanent card with mana value 3 or less from your graveyard to the battlefield. If this spell was cast from a grave$0.39

Return the Favor InstantSpree (Choose one or more additional costs.) + {1} — Copy target instant spell, sorcery spell, activated ability, or triggered abi$0.81

Dualcaster Mage Creature — Human WizardFlash When this creature enters, copy target instant or sorcery spell. You may choose new targets for the copy.$4.42

Reflections of Littjara EnchantmentAs this enchantment enters, choose a creature type. Whenever you cast a spell of the chosen type, copy that spell. (A copy of a pe$3.25

Narset's Reversal InstantCopy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.$3.17

Grapeshot SorceryGrapeshot deals 1 damage to any target. Storm (When you cast this spell, copy it for each spell cast before it this turn. You may $0.37

Isochron Scepter ArtifactImprint — When this artifact enters, you may exile an instant card with mana value 2 or less from your hand. {2}, {T}: You may cop$13.15

Mizzix's Mastery SorceryExile target card that's an instant or sorcery from your graveyard. For each card exiled this way, copy it, and you may cast the c$7.91

Chain of Vapor InstantReturn target nonland permanent to its owner's hand. Then that permanent's controller may sacrifice a land of their choice. If the$15.95

Flare of Duplication InstantYou may sacrifice a nontoken red creature rather than pay this spell's mana cost. Copy target instant or sorcery spell. You may ch$1.87

Plumb the Forbidden InstantAs an additional cost to cast this spell, you may sacrifice one or more creatures. When you do, copy this spell for each creature $0.37

Amphibian Downpour Enchantment — AuraFlash Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.$1.55

Wandering Archaic // Explore the Vastlands Creature — Avatar // SorceryWandering Archaic: Whenever an opponent casts an instant or sorcery spell, they may pay {2}. If they don't, you may copy that spel$8.39

Thousand-Year Storm EnchantmentWhenever you cast an instant or sorcery spell, copy it for each other instant and sorcery spell you've cast before it this turn. Y$1.14

Reverberate InstantCopy target instant or sorcery spell. You may choose new targets for the copy.$2.94

Echoes of Eternity Kindred Enchantment — EldraziIf a triggered ability of a colorless spell you control or another colorless permanent you control triggers, that ability triggers$2.25

Twinning Staff ArtifactIf you would copy a spell one or more times, instead copy it that many times plus an additional time. You may choose new targets f$16.46

Jin-Gitaxias, Progress Tyrant Legendary Creature — Phyrexian PraetorWhenever you cast an artifact, instant, or sorcery spell, copy that spell. You may choose new targets for the copy. This ability t$8.54

Lithoform Engine Legendary Artifact{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy. {3}, {T}: Copy target i$9.13

Primal Amulet // Primal Wellspring Artifact // LandPrimal Amulet: Instant and sorcery spells you cast cost {1} less to cast. Whenever you cast an instant or sorcery spell, put a cha$11.25

Thunderclap Drake Creature — DrakeFlying Instant and sorcery spells you cast cost {1} less to cast. {2}{U}, Sacrifice this creature: When you next cast an instant o$0.54

Kitsa, Otterball Elite Legendary Creature — Otter WizardVigilance Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) {T}: Draw a card, then disc$5.38

Ral, Crackling Wit Legendary Planeswalker — RalWhenever you cast a noncreature spell, put a loyalty counter on Ral. +1: Create a 1/1 blue and red Otter creature token with prowe$12.71

Sword of Wealth and Power Artifact — EquipmentEquipped creature gets +2/+2 and has protection from instants and from sorceries. Whenever equipped creature deals combat damage t$21.44

Arcane Bombardment EnchantmentWhenever you cast your first instant or sorcery spell each turn, exile an instant or sorcery card at random from your graveyard. T$6.19

Grave Researcher // Reanimate Creature — Troll Warlock // SorceryGrave Researcher: At the beginning of your upkeep, surveil 1. Then if there are three or more creature cards in your graveyard, th$1.77

Empty the Warrens SorceryCreate two 1/1 red Goblin creature tokens. Storm (When you cast this spell, copy it for each spell cast before it this turn.)

Reiterate InstantBuyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.) Copy t$19.85

Unbound Flourishing EnchantmentWhenever you cast a permanent spell with a mana cost that contains {X}, double the value of X. Whenever you cast an instant or sor$2.42
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