Cheapest priced copy (Throne of Eldraine): $0.35 at Card Kingdom, near mint, their price list as of .
Festive Funeral 
Instant · Common · Throne of Eldraine · #87
Target creature gets -X/-X until end of turn, where X is the number of cards in your graveyard.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Throne of Eldraine | 87 | Common | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 4 October 2019Festive Funeral is still on the stack while you determine the value of X. It doesn't contribute to the value of X.
- 4 October 2019The value of X is determined only as Festive Funeral begins to resolve. The target creature's power and toughness won't change if other cards are put into your graveyard later in the turn.