This campaign setting is designed for parties of one or two powerful characters. As such, the House Rules have been designed to make characters more powerful than their published counterparts. If you are going to play with a larger group you should take that into account and scale some of those abilities back down, or remove them from your game entirely.
Hundreds of years ago civilization flourished. New “technologies” harnessed the power of spirits and ether to perform miracles. Cities reached to the heavens and civilizations stretched the globe.
Then something went wrong. The spirit world and the Mortal world were ripped apart. Many were driven insane, others were reformed into terrible monsters. The cities fell from the heavens and society collapsed. Even the spirits of nature were ravaged, plunging the world into a never ending winter.
It is now the year 643 AF (After Frost) and criminal syndicates and military states now control the major cities that survived the fall. The great global societies are no more, replaced by warring city-states of crime, corruption, and intrigue.
Even so, the cities are better than the wastes, where any monster you can imagine may dwell, waiting only for your imagination to give it form so it can feed on your spirit and drag you to the abyss.