Scourged World is built on the Apocalypse Game Engine and is designed to be completely compatible with Dungeon World by Sage Kobold Productions, written by Sage LaTorra and Adam Koebel.
However, the Scourged World system adds several new wrinkles to the mix. In addition to the campaign setting, there are a few additional rules, a number of rules clarifications, and tweaks. There are also a number of minor additions to things like weapon and equipment “tags”.
More is added with the implementation of the new playbooks. One aspect of this change is in incorporating the campaign world into the background choices and class designs. 95%+ (roughly) of the playbook material is new. New spells, new moves, etc. Also, some playbooks add additional components to a character. For example, the Favored By Luck playbook introduces a seventh ability and ability score (Luck, [LUC]) for only that character.
Another point of difference is in the treatment of magic items and treasure. Here, Scourged World attempts to bridge the divide between games with an austere magical treasure economy like Dungeon World, and those games with magic shops, potion vending machines, and so on. Somewhere in between those two of extremes is where Scourged World lands. So treasure plays a larger role than in most PbtA games.
What it keeps though is the fundamental frame of the game. 2d6 based Moves, damage dice, etc. The Scourged World game continues to hold firmly onto the narrative approach to gaming.
Other changes…specifically for GMing. I really am fond most of Dungeon World and other PbtA games but the structuring of games used by some of them (using Fronts, Portents, etc.) feels (to me, obviously) regrettably opaque for both novice GMs and GMs new to the game.
The final rules difference has to do with campaign setting and the cultures, societies, etc. in the game. While I still hold to the dictum “draw maps, leave blanks” that sometimes isn’t enough. My campaign setting leaves a lot of blanks but it also fills in a few too. There are detailed cultures and societies sketched out in more detail, but not in the exacting detail of some games. The Scourged World setting includes religions, descriptions of the sentient playable species (that include Dwarves, Elves, Gnomes, Halflings, Humans, and the Igrex), but each is distinctly detailed in terms of culture, religion, customs, social organization, outlook, psychology, and history. Each influences the nature of the many playbooks available.
If you are a Dungeon World fan, these playbooks can easily be used in that system. Indeed, when there is a tag we use that is not part of Dungeon World’s core rules, we also define it in a glossary on the publishing front matter of the playbook. Hopefully, you will be seeing my playbooks available soon on DrivethruRPG. Stay tuned.