Cheapest priced copy (Modern Horizons 2): $0.35 at Card Kingdom, near mint, their price list as of .
Mogg Salvage 
Instant · Uncommon · Nemesis · #94
If an opponent controls an Island and you control a Mountain, you may cast this spell without paying its mana cost.
Destroy target artifact.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $0.35 to $79.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Modern Horizons 2 | 282 | Uncommon | $0.35 | $0.49 |
| Nemesis | 94 | Uncommon | $3.49 | $79.99Out of stock |
4 rulings from Wizards of the Coast
- 18 June 2021Casting a spell without paying its mana cost has no effect on its mana value. Mogg Salvage's mana value is always 3.
- 18 June 2021You don't sacrifice Nevinyrral's Disk to activate its ability. It's destroyed as part of the ability's resolution if it's still on the battlefield. If an effect gives Nevinyrral's Disk indestructible or regenerates it, it stays on the battlefield.
- 18 June 2021To cast Mogg Salvage without paying its mana cost, any opponent may control an Island, not just the one who controls the target artifact.
- 18 June 2021Who controls what lands is important only as you cast Mogg Salvage. Once it has been cast, you no longer controlling a Mountain or each opponent no longer controlling any Islands won't affect Mogg Salvage.