Cheapest priced copy (Ixalan): $0.39 at Card Kingdom, near mint, their price list as of .
Blinding Fog 
Instant · Common · Ixalan · #177
Prevent all damage that would be dealt to creatures this turn. Creatures you control gain hexproof until end of turn. (They can't be the targets of spells or abilities your opponents control.)
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
1 printing · $0.39 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Ixalan | 177 | Common | $0.39 | $0.49 |
2 rulings from Wizards of the Coast
- 29 September 2017Blinding Fog prevents all damage that would be dealt to creatures, not just combat damage.
- 29 September 2017Damage that would be dealt to creatures that enter the battlefield later in the turn will also be prevented. However, creatures that come under your control later in the turn won’t gain hexproof.