This serves as an explanation about the world and the situation in it.
The Anatomy of the Great Tree is as follows
The Canopy is the high-leaf society, mansions made of stone are built onto the massive branches, white marble and golden pathways are built on top of it. No building make sense to exist there, but they found their ways.
The Trunk is a vertical city, with buildings build in and on the side of the Tree, wood is common everywhere, roads are wide and hang over the edges with a void beneath them.
The Roots are for the poor and criminals are sentenced to leave, mud, swamp and roots with moss are everywhere, the buildings are broken from the constant ground changes.
Above the tree in the clouds are floating cities - no human has ever been inside, but they all wonder what is inside the golden glowing palaces. Only ones allowed and able to get in are Angels, that occasionally visit the lower realm of the Great Tree. Of course, they only see the rich top, unaware of the bottom majority.
There is no power system, but magic does exist in this world. Humanity cannot use it normally, however, whenever the Angels visit, they trade or leave their feathers. Those are the source of magic power around here, the more you own, the more power you have.
With 1 feather you can create light, spawn water, blind someone or help with your work. They are insanely expensive and wanted by all.