No one could have imagined that the once peaceful world would be irretrievably lost. One day, everything fell apart, and the world turned into a massive pyramid. Various of creatures found homes on different "layers", each based on how high or low they were. With no physical paths connecting these layers, we could only travel using huge "portals".
The surviving humans live in the lowest, poorest areas of this new world. They call it the "Tower of Shards" and hope to reach the top of the world one day, breaking free from an unfair destiny.
While we won't give in to this strange fate, only a few people, known as "the Marked", can safely travel through the "portals". They're our last hope.
Since humans are living in areas with few resources, it's up to "the Marked" to start expeditions to bring back resources home.