they live in domes that pretend it's all safe and sound. If you look up, you see the 'sky' is a bunch of squares, hence, it's a fake illusion of a sky/world. they did this before, and it was mentioned in the scrolls in the first game that they lived in the domes, and the sky illusion was there too.
Yeah I know, but they have domes that simulate that stuff. You can also see buildings below you if you look.
technology is the word, people