Planescape Rapture

In the centre of all existence there lies a land that connects heavens and hells, and in the middle of that land a floating at the top of infinite Spire, a ring-shaped city that has infinitive doors to all planes in the multiverse. The City of Doors also known as Sigil is home to all the races from the noble githzeria warriors to cunning yugoloth fiends. Ruled by a silent and deadly Lady of Pain, this land is somehow a sanctuary that neither gods or demons dare to disturb. 15 Factions each with their radical ideologies governs the city, living under in a forced peace but all will change as some greedy Factors are planning for a war.
As players,you will be part of a Mercenary gang; who do various things for Factions or those who need help and pay. Instead of being good guys, this is a mercenary game where you don't have to do follow alignments, try to do things for any boss figures.

1) All the races/ classes from Wizard of the Coast books are permitted (even if they are in beta).
2) We use random 4 out of 3 rolls (allowed to roll three arrays and choose the best one). You can take regular hit point or roll (if you roll you cannot take half.)
3) You are starting from 9th level.
3) Being part of a faction will give you powers.
4) Combat can be a little bit more deadly.
5) We use sane magical prices, but there would be less magical weapons and other resistance breaking items.
6) A different take on inspiration.
8) There will be planer rules and some of them you will have to discover as you travel.
9) A new experience system, the 3 pillars system https://media.wizards.com/2017/dnd/downloads/UA-ThreePillarXP.pdf

A couple of links for if you want to learn more about the Factions and the world:
https://en.wikipedia.org/wiki/Planescape
https://en.wikipedia.org/wiki/Sigil_(Dungeons_%26_Dragons)
https://en.wikipedia.org/wiki/Faction_(Planescape) Please only look at original factions.
There is also this old looking site. http://mimir.net/factions/