Cheapest priced copy (Duel Decks: Speed vs. Cunning): $0.35 at Card Kingdom, near mint, their price list as of .
Arrow Volley Trap 
Instant — Trap · Uncommon · Zendikar · #2
If four or more creatures are attacking, you may pay {1}{W} rather than pay this spell's mana cost.
Arrow Volley Trap deals 5 damage divided as you choose among any number of target attacking creatures.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Duel Decks: Speed vs. Cunning | 71 | Uncommon | $0.35 | — |
| Zendikar | 2 | Uncommon | $0.35 | $0.49 |
4 rulings from Wizards of the Coast
- 1 October 2009You divide the damage as you cast Arrow Volley Trap, not as it resolves. Each target must be assigned at least 1 damage.
- 1 October 2009Casting a Trap by paying its alternative cost doesn’t change its mana cost or mana value. The only difference is the cost you actually pay.
- 1 October 2009Effects that increase or reduce the cost to cast a Trap will apply to whichever cost you chose to pay.
- 1 October 2009You may ignore a Trap’s alternative cost condition and simply cast it for its normal mana cost. This is true even if its alternative cost condition has been met.