Cheapest priced copy (Mercadian Masques): $0.35 at Card Kingdom, near mint, their price list as of .
Ferocity 
Enchantment — Aura · Common · Mercadian Masques · #245
Enchant creature
Whenever enchanted creature blocks or becomes blocked, you may put a +1/+1 counter on it.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
1 printing · $0.35 to $2.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Mercadian Masques | 245 | Common | $0.35 | $2.49 |