Cheapest priced copy (March of the Machine): $0.35 at Card Kingdom, near mint, their price list as of .
Change the Equation 
Instant · Uncommon · March of the Machine · #50
Choose one —
• Counter target spell with mana value 2 or less.
• Counter target red or green spell with mana value 6 or less.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
1 printing · $0.35 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| March of the Machine | 50 | Uncommon | $0.35 | $0.99 |
One ruling from Wizards of the Coast
- 14 April 2023If a spell has {X} in its mana cost, use the value chosen for X when calculating that spell’s mana value.