It is card 3 of the 132 in the official Gym Challenge checklist. If you are completing the set, mark it in your collection to keep track.
Rarity: Holo Rare. The symbol in the bottom corner confirms it at a glance, as explained in Pokémon card rarities explained.
It exists in several finishes (Holo, 1st edition). Each one has its own price; the average above is for the regular version.
Artwork by Ken Sugimori. Some collectors chase every card by the same artist: how to start (in Spanish).
Abilities
Shapeshift Pokemon Power
Once during your turn (before your attack), you may attach an Evolution card from your hand to Brock's Ninetales. (This doesn't count as evolving Brock's Ninetales.) Treat Brock's Ninetales as if it were that Pokémon instead. It can't evolve, devolve, or use the Pokémon Power of that Pokémon. During your turn, you may discard the Evolution card attached to Brock's Ninetales. This power can't be used if Brock's Ninetales is Asleep, Confused, or Paralyzed. If Brock's Ninetales becomes Asleep, Confused, or Paralyzed, discard all Evolution cards attached to it.
