Koga's Arbok is a Rare Pokémon — Stage 1 card from Pokémon TCG (Gym Challenge, GYM2).
Rare
Gym Challenge (GYM2)
Card Text
Poison Buildup: Koga's Arbok is now Poisoned.
Poison Power: If Koga's Arbok is Poisoned, this attack's base damage is 40 instead of 20 and the Defending Pokémon is now Poisoned.