Cheapest priced copy (Avatar: The Last Airbender Eternal): $0.99 at Card Kingdom, near mint, their price list as of .
Crystalline Armor 
Enchantment — Aura · Rare · Avatar: The Last Airbender Eternal · #204
Enchant creature
Enchanted creature gets +1/+1 for each land you control and has trample.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $0.79 to $1.29 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Avatar: The Last Airbender Eternal | 137 | Rare | $0.99 | $0.79 |
| Avatar: The Last Airbender Eternal | 204 | Rare | $1.29 | $0.99 |