A Ninja Gecko, and a Samurai Dragon. I did see these two working together at points, but they do have some opposing values. Gaonaga is about facing any opponent that challenges him. Kagiza is the kind of guy to avoid fights, but will do lots of harm when he has to. And I imagine Gaonaga wouldn't be impressed much with a guy who does a lot of hiding and striking from the shadows. But then, I guess the Feudal Japan Samurai was secretly glad to have a ninja backing him up when the Shogun hired them, even though Samurai outright and publicly condemned Ninjas for their tactics. Still, there is a chance that these two after their first meeting, would have a relationship very similar to Godzilla and Anguirus. And again, these two do have similar goals as someone pointed out, but they have somewhat different methods of getting to that goal. Still, should be interesting to see what this game does with them.
Ninja Space Gecko? Interesting. But he just, is, coming from Space as a fully formed Kaiju with no origin but being born that way. Oh well, I guess the idea is that Kaiju stalk space all over the galaxy, and that there are indeed whole species who are naturally Kaiju other there in the galaxy. That is a rather interesting concept I guess.