Cheapest priced copy (Conspiracy: Take the Crown): $0.35 at Card Kingdom, near mint, their price list as of .
Vertigo Spawn 
Creature — Illusion · 0/3 · Uncommon · Guildpact · #42
Defender
Whenever this creature blocks a creature, tap that creature. That creature doesn't untap during its controller's next untap step.
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 | 125 | Uncommon | $0.35 | $0.49 |
| Guildpact | 42 | Uncommon | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 1 February 2006If the creature was already tapped when Vertigo Spawn blocked it, that creature still won't untap during its controller's next untap step.
- 1 February 2006If two Vertigo Spawns block the same creature, both abilities trigger, but each only affects the creature during its controller's next untap step. The creature can untap during its controller's untap step following that one.