Koga sent Arbok to pursue Red and Blue from the Pokémon Tower. Arbok spit Acid out, which Red and Blue narrowly dodged. Charmeleon used Reflect to prevent attacks, but Arbok spit more acid out and melted Charmeleon down. However, to Koga's disdain, the Pokémon was a dead Psyduck, and the actual Charmeleon defeated Arbok, causing its body to be split into two pieces. At the Pokémon League, while Blue and Red were fighting, Professor Oak had a flashback of Koga's Arbok. He noted the way Blue defeated Arbok, with instinct and calm attitude, was passed onto Red, as he continued battling without losing his temper.
Koga sent Arbok and came on it to face Agatha's Arbok. However, Agatha's Arbok changed its color pattern and wrapped its tail around Koga and his Arbok. As an attempt to break free, Koga's Arbok used Glare, but Agatha's Arbok resisted the attack, by changing its color pattern once more. In addition, Agatha's Arbok attacked Koga's Arbok, biting its tail off. After Koga threw shurikens to Blue (to assist him in defeating Agatha's Golbat), his Arbok regenerated its tail. Koga called his Arbok back, as the leftover tail, which was moving on Arbok's will, provided a trap to lure Agatha's Gengar in, who was defeated by Blue's Porygon.