Cataclysm: 7 chapters

The world has ended, but humanity, has not...
After centuries of war, conflict death, and carnage. The factions of the eastern region have finally found peace...
Until one day, a barbaric nation of murderers, thieves, and criminals arrive on the doorsteps of the eastern region.
Now, the Nations of the East must overcome past quarrels to defeat their common enemy.

Cataclysm is a novel that combines elements of Sci-Fi, Fantasy, and the Post apocalyptic genres, and is inspired by books like The Expanse, The Dark Tower, Attack On Titan, The Hunger Games and A Song of Fire and Ice.
I'd appreciate criticism. I want to Grow as a story teller, feel free to rip this to shreds.