Eric was punching, kicking, and sending a flurry of attacks towards his targets, having no intention of allowing them a moment of rest.
His actions of kicking them while they were down might be called weak, and cowardly but he didn't really care.
He had no reason to play the stupid good guy that would allow them to regain their strength, only to win the fight while suffering.
That was bullshit!
He had this great chance of beating them while they were down and teaching them a lesson in case they didn't obey or didn't lower their heads.
Whether they liked it or not, the Salamander General, or the Crab Leader had no other option but to obey and belong to him from now on.
Of course, while he was beating the crap out of them, he didn't forget to release the Dragon Aura inside himself as well, having the two beasts fear him as an entity.