Make everything cheaper, by type, by colour, or across the board. Two of these together is how a storm turn starts.
85%Herald's Horn ArtifactAs this artifact enters, choose a creature type. Creature spells you cast of the chosen type cost {1} less to cast. At the beginni$5.76
84%Foundry Inspector Artifact Creature — ConstructArtifact spells you cast cost {1} less to cast.$0.37
92%Jet Medallion ArtifactBlack spells you cast cost {1} less to cast.$12.86
93%Ruby Medallion ArtifactRed spells you cast cost {1} less to cast.$14.12
90%Urza's Incubator ArtifactAs this artifact enters, choose a creature type. Creature spells of the chosen type cost {2} less to cast.$21.50
94%Sapphire Medallion ArtifactBlue spells you cast cost {1} less to cast.$8.17
87%Etherium Sculptor Artifact Creature — Vedalken ArtificerArtifact spells you cast cost {1} less to cast.$0.73
91%Pearl Medallion ArtifactWhite spells you cast cost {1} less to cast.$6.73
84%Ghalta, Primal Hunger Legendary Creature — Elder DinosaurThis spell costs {X} less to cast, where X is the total power of creatures you control. Trample (This creature can deal excess com$1.06
90%Goblin Anarchomancer Creature — Goblin ShamanEach spell you cast that's red or green costs {1} less to cast.$1.19
93%Emerald Medallion ArtifactGreen spells you cast cost {1} less to cast.$6.12
89%Emry, Lurker of the Loch Legendary Creature — Merfolk WizardAffinity for artifacts (This spell costs {1} less to cast for each artifact you control.) When Emry enters, mill four cards. {T}: $0.57
93%Cloud Key ArtifactAs this artifact enters, choose artifact, creature, enchantment, instant, or sorcery. Spells you cast of the chosen type cost {1} $1.57
87%Goreclaw, Terror of Qal Sisma Legendary Creature — BearCreature spells you cast with power 4 or greater cost {2} less to cast. Whenever Goreclaw attacks, each creature you control with $5.81
93%Goblin Electromancer Creature — Goblin WizardInstant and sorcery spells you cast cost {1} less to cast.$0.31
92%Bontu's Monument Legendary ArtifactBlack creature spells you cast cost {1} less to cast. Whenever you cast a creature spell, each opponent loses 1 life and you gain $4.44
94%The Earth Crystal Legendary ArtifactGreen spells you cast cost {1} less to cast. If one or more +1/+1 counters would be put on a creature you control, twice that many$13.67
82%Thought Monitor Artifact Creature — ConstructAffinity for artifacts (This spell costs {1} less to cast for each artifact you control.) Flying When this creature enters, draw t$0.28
90%Danitha Capashen, Paragon Legendary Creature — Human KnightFirst strike, vigilance, lifelink Aura and Equipment spells you cast cost {1} less to cast.$0.97
93%The Fire Crystal Legendary ArtifactRed spells you cast cost {1} less to cast. Creatures you control have haste. {4}{R}{R}, {T}: Create a token that's a copy of targe$5.99
87%Thoughtcast SorceryAffinity for artifacts (This spell costs {1} less to cast for each artifact you control.) Draw two cards.$3.37
94%Archmage of Runes Creature — Giant WizardInstant and sorcery spells you cast cost {1} less to cast. Whenever you cast an instant or sorcery spell, draw a card.$3.30
93%Stormcatch Mentor Creature — Otter WizardHaste Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) Instant and sorcery spells you $0.34
92%The Wind Crystal Legendary ArtifactWhite spells you cast cost {1} less to cast. If you would gain life, you gain twice that much life instead. {4}{W}{W}, {T}: Creatu$6.93
81%Omniscience EnchantmentYou may cast spells from your hand without paying their mana costs.$6.38
94%Oketra's Monument Legendary ArtifactWhite creature spells you cast cost {1} less to cast. Whenever you cast a creature spell, create a 1/1 white Warrior creature toke$6.23
89%Jhoira's Familiar Artifact Creature — BirdFlying Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)$2.52
91%Ugin, the Ineffable Legendary Planeswalker — UginColorless spells you cast cost {2} less to cast. +1: Exile the top card of your library face down and look at it. Create a 2/2 col$2.26
89%Nightscape Familiar Creature — ZombieBlue spells and red spells you cast cost {1} less to cast. {1}{B}: Regenerate this creature.$0.40
89%Starfield Mystic Creature — Human ClericEnchantment spells you cast cost {1} less to cast. Whenever an enchantment you control is put into a graveyard from the battlefiel$0.33
Prices and legality come from Scryfall. Every card here was scored by the same search that runs when you type a question.
