Cheapest priced copy (Scars of Mirrodin): $0.35 at Card Kingdom, near mint, their price list as of .
Carapace Forger 
Creature — Elf Artificer · 2/2 · Common · Scars of Mirrodin · #114
Metalcraft — This creature gets +2/+2 as long as you control three or more artifacts.
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Scars of Mirrodin | 114 | Common | $0.35 | $0.49 |