Cheapest priced copy (Conspiracy: Take the Crown): $0.35 at Card Kingdom, near mint, their price list as of .
Merfolk Skyscout 
Creature — Merfolk Scout · 2/3 · Uncommon · Rise of the Eldrazi · #77
Flying
Whenever this creature attacks or blocks, untap target permanent.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Conspiracy: Take the Crown | 115 | Uncommon | $0.35 | $0.49 |
| Rise of the Eldrazi | 77 | Uncommon | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 15 June 2010When Merfolk Skyscout blocks, its second ability triggers just once, even if it somehow blocked multiple attacking creatures.
- 15 June 2010You may target any permanent with the ability, including Merfolk Skyscout itself or a permanent that’s already untapped.