Rex has been focused on his training entirely, wanting to learn the Brutal Impulse Moon Ability.
Without any additional skill that made him stronger would only put himself in much more danger, there are too many uncertainties that are surrounding him and the others right now. It was all due to the fact they were forced to get out of humanity's territory.
Although he knows it will be hard, he didn't quite expect to get this kind of problem.
One of the worst impacts of getting out of the human territory is the fact that he also got cut off from accessible information, he's completely cut off from the outside world and now doesn't know what's happening.
No technology to give him some news, and there are also no people to update him.
