His specialty is with electric Pokémon. He said that his electric Pokémon aided him in the war by electrifying and paralyzing his foes.
In the manga he was one of the core members of Team Rocket. He was equipped with weaponry that uses Pokémon as power sources. He has a suit called Electric Underwear that is able to absorb electricity from even the legendary Zapdos. He is able to use Magneton as shoulder pads that are able to erect a magnetic force field.
He was power hungry and joined Team Rocket for his desire of a greater possession than just being a Gym Leader.