Cheapest priced copy (Eventide): $4.99 at Card Kingdom, near mint, their price list as of .
Primalcrux 
Creature — Elemental · */* · Rare · Eventide · #73
Trample
Chroma — This creature's power and toughness are each equal to the number of green mana symbols in the mana costs of permanents you control.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
1 printing · $4.99 to $16.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Eventide | 73 | Rare | $4.99 | $16.99 |
3 rulings from Wizards of the Coast
- 1 August 2008This will count the number of symbols in its mana cost while it's on the battlefield. The ability functions while it's in other zones, but since it isn't a permanent while in those zones it won't count itself.
- 1 August 2008Chroma abilities check only mana costs, which are found in a card's upper right corner. They don't count mana symbols that appear in a card's text box.
- 1 August 2008Chroma abilities count hybrid mana symbols of the appropriate color. For example, a card with mana cost {3}{U/R}{U/R} has two red mana symbols in its mana cost.