Well we have to consider something...
What if he isn't the champion, and Kotal maybe mistook him as such? Johnny is too smug to admit otherwise and it would explain Sonya's... exasperation with it all. Not saying he isn't playable, but just maybe another moment of Johnny being Johnny.
If he is thats awesome, but I don't pin him as someone who would be like "No I'm not the champion, you have some other guy mistaken for me".
Way to stretch. Johnny Cage's potential to take the mantle after Liu Kang was already there since Armaggedon, check out his bio-kard.
The champion thing though could go both ways, him being in fact Raiden's finest or just a manner of speaking to another earthrealm warrior, i asked Kittelsen on twitter about this and here is his answer:
https://twitter.com/kittelsen/status/570796617944555520
I understand that, he meant that this is an inside information, which would gravitate towards him being the real deal, but, they can't reveal much more yet, because it's something that would affect at least partially the story of the game, which most likely will cover the Netherrealm war and will reveal more details.
Regardless, some people keep calling JC a fool and comic relief only, but did you see the way he handled the situation? he was on point, Sonya once again was hostile, where JC was much more level headed and managed to end the animosity, and at that moment he took the lead over Sonya, who was a veteran on the Special Forces whereas he is relatively new there, being only an actor in the previous years. I think this comic itself already showed how the character has already evolved.
lol
