After burner is the Charizard of Todd [link]
who went fighting team rocket. The base that they went to was working on experiments to boost Pokemon abilities. One of the particular experiments was a serum that was meant to cause a 3rd like evolution to already fully evolved Pokemon. The only problem with the serum was that is overwhelmed all the Pokemon exposed, killing them. Because of this, the leader of the base used it like a weapon. He injected Todds Charizard with it but after hours of excruciating pain After Burner pulled through. He was already many time bigger and was a lot more dragon like. He then saved Todd from the rocket boss by eating the boss and continued to burn down the base after everybody fled from it. He later excreted the slightly bleached and smelly Rocket boss.
I'm nearly finished Todds whole group. Just Alakazam left to finish. I am just a very lazy person.