Cheapest priced copy (Avatar: The Last Airbender Eternal): $0.99 at Card Kingdom, near mint, their price list as of .
The Duke, Rebel Sentry 
Legendary Creature — Human Rebel Ally · 0/1 · Uncommon · Avatar: The Last Airbender Eternal · #76
The Duke enters with a +1/+1 counter on him.
{T}, Remove a counter from The Duke: Put a +1/+1 counter on another target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
1 printing · $0.99 to $1.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Avatar: The Last Airbender Eternal | 76 | Uncommon | $0.99 | $1.99 |