Zach and Asmodeus' main goal was to travel and reach the capital to easily access the inner hell gate, and whatever happened to them in their way was nothing but a nuisance.
They had wasted an hour fighting monsters in the hell's spawn, and there was no end to them. After Zach came up with an idea to deal with them, they had to wait for the domain caster to appear in front of them.
However, they didn't necessarily have to wait for the caster to move forward. They could continue their journey while still staying in the hell's spawn as it followed them anywhere.
The domain caster had trapped Zach and Asmodeus to an eternal hell's spawn, which they would never be able to escape; they were caged. However, the same cage was now protecting them from other monsters, as no one could enter inside the domain from outside or escape from inside.
Needless to say, Zach and Asmodeus continued walking without caring for the caster.
