Cheapest priced copy (Adventures in the Forgotten Realms): $0.35 at Card Kingdom, near mint, their price list as of .
Price of Loyalty 
Sorcery · Common · Adventures in the Forgotten Realms · #159
Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. If mana from a Treasure was spent to cast this spell, that creature gets +2/+0 until end of turn.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Adventures in the Forgotten Realms | 159 | Common | $0.35 | $0.49 |