Viper

Viper is a character of the day in Pokémon Chronicles, who appeared in Training Daze. He is the Drill Sergeant of the Team Rocket Academy and trains new recruits for Team Rocket.

He was impressed by Butch and Cassidy's teamwork, as well as Jessie, despite the fact that she had gone through several partners over two months. Viper reported to Giovanni that Jessie should receive further training because she contains a special quality unseen in anyone else. The Team Rocket Boss agreed with the recommendation and Viper formally introduced Jessie, James, and Meowth to each other before they could officially declare themselves a part of Team Rocket.

Viper provided clear instructions to each of the training rounds, and was disguised as a red Snorlax for the final trial. At the Team Rocket Academy graduation ceremony, he declared Jessie, James, and Meowth fledgling members of Team Rocket, while Butch and Cassidy were granted the villains-in-training status.

(Source: Bulbapedia)