Role in the series
Not long after Caine's arrest, Axel and another thief known as Dwayne formed a plan to get her out and to steal Corona's gold that is to be transported in one swoop. To gain the trust of the Royal guards, the two put on an act where Axel helps them in catching Dwayne and the darkly coated steed lying to them about having no home or owner to take care of him; which later got him a place in the royal guard. While everyone was beginning to love the new royal guard horse, Maximus was the only one that uncovered their plan. By seeing and spending with the true Axel and uncovering a wanted poster of him being ridden by Dwayne.
When it looked like that everything had gone according to plan, Maximus had managed to reveal the truth to the others and he and Rapunzel gave chase. Which led to the escapees being caught, once again, while Axel landed in a pile of mud.
Axel returns in "Max and Eugene in Peril on the High Seas", when he and a few other criminals take over a prison ship.