Like most Pokmon cards, the value of Vulpix depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Fusion Strike)
Although it was never confirmed, these E ITION markings of the Base Ghost/Phantom Pikachu might have been added during the printing process as indication, so the 1st edition stamps would be properly aligned (which kinda failed in most cases)
True to the Pokmon it depicts, this card features two exciting variants
Its powerful because a 2/2 for a single mana is well above rate
It's a formula that appears in Final Fantasy time and again, and one that players can revisit if they are to head back to prior releases
You can also see the main features for each one