Cheapest priced copy (Mirrodin): $0.35 at Card Kingdom, near mint, their price list as of .
Roar of the Kha 
Instant · Uncommon · Mirrodin · #18
Choose one —
• Creatures you control get +1/+1 until end of turn.
• Untap all creatures you control.
Entwine {1}{W} (Choose both if you pay the entwine cost.)
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Mirrodin | 18 | Uncommon | $0.35 | $0.49 |