From Bulbapedia, the community-driven Pokémon encyclopedia.
Gordon (Japanese: サトル Satoru) is a character of the day in the Pokémon anime. He appeared in Absol-ute Disaster.
Gordon and his younger brother Nicky lived in Riyado Town. The town had a problem with an Absol. Every time it appeared, something bad happened. The town blamed Absol for everything that was happening, but Gordon refused to believe it. In search of answers, he went looking for the Absol. When he failed to return, the town believed the Absol got to him.
Nicky, along with Ash and his friends, went to find out what happened to Gordon. When Nicky and Max fell off a cliff, Gordon and his Heracross came to their rescue. Gordon revealed that the Absol had saved his life, so he decided to spend some time studying it. That was when he discovered Riyado Town was about to be flooded.
Using all their Pokémon, the group was able to stop the imminent flood by knocking down a boulder. The town soon apologized to Absol and Gordon. The town then considered Absol a hero rather than an enemy.
The listing is of Gordon's known Pokémon: