Affinity

Affinity
Keyword Ability
Type	Static
Introduced	Mirrodin
Last used	Modern Horizons 2
Reminder Text	Affinity for [text] (This spell costs less to cast for each [text] you control.)
Storm Scale	6
Statistics	22 Affinity for artifacts cards 4.5% 50% 9.1% 4.5% 4.5% 27.3% 1 Affinity for Plains card 100% 1 Affinity for Islands card 100% 1 Affinity for Swamps card 100% 1 Affinity for Mountains card 100% 1 Affinity for Forests card 100% 1 Affinity for Tokens card 100%
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keyword:"Affinity"

Affinity is a keyword ability that reduces the mana cost of a spell by the number of permanents of a certain type that player controls. It appeared in the Mirrodin block.

Description

The ability is always written as "Affinity for [something]". The most common instance is "Affinity for artifacts" (see Frogmite). However, a cycle of Golems (consisting of Dross Golem, Oxidda Golem, Razor Golem, Spire Golem, and Tangle Golem) appeared in the Darksteel expansion, each with affinity for a particular basic land type. Hum of the Radix functions as an "anti-affinity" enchantment, increasing by 1 the cost of all artifact spells for each artifact its controller owns. Mycosynth Golem grants affinity to artifacts for all artifact creature spells cast by its controller, in addition to having affinity for artifacts itself.

Almost all tournament-legal cards with affinity were printed during the Mirrodin block, and contributed heavily to the Second Combo Winter. The mechanic was considered for a return in the Scars of Mirrodin block, but rejected because it had been so destructive for the metagame in its first appearance.

Affinity appeared as a one-off in War of the Spark with Tezzeret, Master of the Bridge.

Affinity was reintroduced in Modern Horizons 2, using new variants such as "Affinity for tokens" (Junk Winder).

Unkeyworded affinity

With cost-reduction being so powerful and the format-warping effects of affinity for artifacts, the mechanic has not been revisited. However, single cards have been printed that fit the rules text but are not keyworded to save keyword learning space. Saheeli, the Gifted (Commander 2018), Gearseeker Serpent (Kaladesh), Emry, Lurker of the Loch (Throne of Eldraine) and Reality Heist are those that still use artifacts.

Other objects include:

• Gate Colossus (Gates)
• Embercleave (attacking creatures)
• The Circle of Loyalty (Knights)
• Brine Giant and Sky-Blessed Samurai (enchantments)
• Hamza, Guardian of Arashin (creatures with +1/+1 counters, also grants it to your other creature spells)
• Icebreaker Kraken (snow lands)
• Millicent, Restless Revenant (Spirits)
• Walking Skyscraper (modified creatures)
• Angelic Observer (Citizens)

Ten spells that care about Party have "Affinity for creatures in your Party", but the wording for Party and the wording of Affinity mix poorly. In a similar vein:

• Stratadon has "Affinity for Domain"; Draco and Scion of Draco have "Affinity for Domain" twice.
• Valiant Changeling has "Affinity for creature types".
• Drag to the Underworld and Marshmist Titan have "Affinity for devotion to black"; Daybreak Chimera has "Affinity for devotion to white"
• Khalni Hydra has a unique version where the cost reduced is rather than , but otherwise has "Affinity for green creatures".

The next list does not require controlling the objects to discount, such as a certain quality of players, cards in other zones, or other player's creatures.

• Blasphemous Act, Vanquish the Horde (creatures)
• Primeval Protector (opponent's creatures)
• Diregraf Rebirth, Blood for the Blood God! (creatures that have died)
• Stone Idol Trap, Ancient Stone Idol (anyone's attacking creatures)
• Search Party Captain, Gnoll Hunting Party (creatures declared as attackers)
• Obsidian Charmaw (opponent's lands that produce )
• Ghoultree, Karador, Ghost Chieftain, Molderhulk, Nemesis of Mortals, Writhing Necromass, The Cauldron of Eternity (creatures in your graveyard)
• Bedlam Reveler, Cryptic Serpent, The Magic Mirror (instants/sorceries in your graveyard)
• Sailor's Bane (instants/sorceries in graveyard and exile, plus exiled Adventure creatures)
• Ore-Scale Guardian (lands in graveyard)
• Emrakul, The Promised End (different types in graveyard)
• Oskar, Rubbish Reclaimer (different mana values in graveyard)
• Avatar of Growth, all spells with Undaunted (opponents)
• Gnoll War Band (damaged opponents)
• Gnoll Hunting Party (opponents attacked that turn)
• Astral Confrontation (attacked opponents by you)
• Tolarian Terror (instants/sorceries in graveyard)

Rules

From the glossary of the Comprehensive Rules (June 7, 2024—Modern Horizons 3)

Affinity

A keyword ability that reduces how much mana you need to spend to cast a spell. See rule 702.41, “Affinity.”

From the Comprehensive Rules (June 7, 2024—Modern Horizons 3)

• 702.41. Affinity
  • 702.41a Affinity is a static ability that functions while the spell with affinity is on the stack. “Affinity for [text]” means “This spell costs you {1} less to cast for each [text] you control.”
  • 702.41b If a spell has multiple instances of affinity, each of them applies.

Rulings

• The affinity ability reduces only the amount of generic mana you pay. It can't reduce how much nongeneric mana you pay.
• Affinity can't reduce the cost to cast a spell to less than .
• Affinity doesn't change the spell's mana cost or converted mana cost. It just changes how much mana you pay to cast the spell.
• The cost reduction is set before you have to pay any costs for the spell. If you sacrifice an artifact while paying the spell's costs, that artifact still counts toward the cost reduction.

Examples

Example

Into Thin Air
Instant
Affinity for artifacts (This spell costs less to cast for each artifact you control.)
Return target artifact to its owner's hand.

Notable cards with affinity

Frogmite, Myr Enforcer, Thoughtcast - used in affinity decks