Cheapest priced copy (Duskmourn: House of Horror): $0.49 at Card Kingdom, near mint, their price list as of .
Leyline of Mutation 
Enchantment · Rare · Duskmourn: House of Horror · #188
If this card is in your opening hand, you may begin the game with it on the battlefield.
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
4 printings · $0.49 to $1.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Duskmourn: House of Horror | 188 | Rare | $0.49 | $0.49 |
| Duskmourn: House of Horror | 382 | Rare | $0.49 | $0.99 |
| Duskmourn: House of Horror Promos | 188p | Rare | $0.49 | $0.99 |
| Duskmourn: House of Horror Promos | 188s | Rare | — | $1.79Out of stock |
4 rulings from Wizards of the Coast
- 20 September 2024If you cast a spell for another cost "rather than pay" its mana cost, you can't choose to cast it for any other alternative cost. You can, however, pay additional costs. If the spell has any mandatory additional costs, such as that of Abhorrent Oculus, those must be paid to cast the spell.
- 20 September 2024A player's "opening hand" is the hand of cards the player has after all players have taken mulligans. If players have any cards in hand that allow actions to be taken with them from a player's opening hand, the starting player takes all such actions first in any order, followed by each other player in turn order. Then the first turn begins.
- 20 September 2024If you cast a spell for which mana may be spent as though it were mana of any color, you may cast it for Leyline of Mutation's second ability's alternative cost and still spend mana as though it were mana of any color.
- 20 September 2024If a spell has {X} in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.