The Rift Between Cities: The Uprisers

(No system, no overpowered protagonist, plot-driven, focus on human nature, not a typical power fantasy)(Character growth: the protagonist's personality evolves with the plot)(Ensemble cast: supporting characters are multi-dimensional and react emotionally to their changing environment)

In this world, divided in two at some unknown point in history:

The people of the Upper City live under the sun, with vast lands, warmth, and freedom. Those in the Lower City exist in dark, cramped underground spaces, never seeing daylight, where even breathing can be fatal.

In a dim alley, a deranged old man, guzzling cheap liquor, throws back his head and howls with laughter:

"Oh, noble lords of the Upper City! In your eyes, do we of the Lower City... even count as human?"