Cheapest priced copy (Outlaws of Thunder Junction): $0.35 at Card Kingdom, near mint, their price list as of .
Redrock Sentinel 
Artifact Creature — Golem · 2/4 · Uncommon · Outlaws of Thunder Junction · #247
Defender
{2}, {T}, Sacrifice a land: Draw a card and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Outlaws of Thunder Junction | 247 | Uncommon | $0.35 | $0.49 |