He is certanly up to no good with someone or some other people but we do not know who yet.
I may involve something to do with taking over the realms with the aid of someone and then the deception would take place from there, But like with almost all news at the moment its not known what the actualy plot is with 90% of the characters and storylline.

I think he will align with one of earth's strongest warriors(Liu), and in the end he will deceive his partner.

I think the whole aura of the Dragon King is amazing!!!!!! And I think the deceptive part will be truly deceptive. Like, you'll have to beat the game to find out. It could be a number of things.