Cheapest priced copy (Stronghold): $0.35 at Card Kingdom, near mint, their price list as of .
Furnace Spirit 
Creature — Spirit · 1/1 · Common · Stronghold · #87
Haste
{R}: This creature gets +1/+0 until end of turn.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
1 printing · $0.35 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Stronghold | 87 | Common | $0.35 | — |