Cheapest priced copy (Antiquities): $5.49 at Card Kingdom, near mint, their price list as of .
Mightstone 
Artifact · Uncommon · Antiquities · #55
Attacking creatures get +1/+0.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
1 printing · $5.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Antiquities | 55 | Uncommon | $5.49 | — |
One ruling from Wizards of the Coast
- 4 October 2004The +1/+0 applies to attacking creatures from all players.