Cheapest priced copy (Duel Decks: Heroes vs. Monsters): $0.35 at Card Kingdom, near mint, their price list as of .
Armory Guard 
Creature — Giant Soldier · 2/5 · Common · Duel Decks: Heroes vs. Monsters · #12
This creature has vigilance as long as you control a Gate.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
3 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Duel Decks: Heroes vs. Monsters | 12 | Common | $0.35 | — |
| Return to Ravnica | 2 | Common | $0.35 | $0.49 |
| Ravnica Remastered | 3 | Common | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 1 October 2012Vigilance only matters when Armory Guard is being declared as an attacking creature. If Armory Guard is already attacking, losing control of your only Gate won’t cause Armory Guard to become tapped or to leave combat.