Literally just thinking of Starter Squad and I had an idea of a Pokémon who decided to leave the Squad for life of crime.

This Pokémon name is Turbo. I just thought of the line in Wreck it Ralph for the name. Anyways, he's a Pikachu that loves to run and he's the fastest runner in the Squad which gives him a great advantage as a crime fighter and a criminal now.

His moveset:
Volt Tackle
Quick Attack
Electro Ball
Agility

He loved running as a Pichu and it soon grew on him. He thinks he's faster than a Ninjask. He won the running marathon for 5 years (since he joined in. He never lost)

Turbo is a thief and sometimes when he runs into someone with great force, they die from the strong blow. Due to this, he is considered a very dangerous criminal.