Cheapest priced copy (Kaladesh): $0.49 at Card Kingdom, near mint, their price list as of .
Eliminate the Competition 
Sorcery · Rare · Kaladesh · #78
As an additional cost to cast this spell, sacrifice X creatures.
Destroy X target creatures.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
3 printings · $0.49 to $0.69 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Kaladesh | 78 | Rare | $0.49 | $0.49 |
| Kaladesh Promos | 78s | Rare | — | $0.69 |
| Tarkir: Dragonstorm Commander | 179 | Rare | $0.49 | — |
2 rulings from Wizards of the Coast
- 20 September 2016If you somehow cast Eliminate the Competition without paying its mana cost, you'll still choose a value for X and sacrifice X creatures.
- 20 September 2016Once you announce that you're casting Eliminate the Competition, players can't try to remove creatures you'd like to sacrifice.