Noah didn't leave the mountain chain immediately. His stash of magical beasts' corpses had grown thin in the last period, and that danger zone was the best place to refill it.
Also, Snore was still becoming used to its body. Coupling its training with his hunts would settle both issues faster.
The Demonic Sword had advanced too, which meant that Noah had to test his battle prowess once again.
Noah spent weeks hunting in the mountain chain to tune his battle style to his new assets. Still, his mind was elsewhere most of the time since he had yet to decide what he would do next.
There were many projects available in front of him. He had yet to create a training method for his sea of consciousness, and he didn't even begin to fuse spells and martial arts.
There was a lot to research with the dark matter too. Noah had only started to use his higher energy as a material, but it contained too much power to be limited in that single field.