Editing Blood War (section)

==In 5e==
The Blood War returned in 5th edition, covered in the first chapter of ''Mordenkainen's Tome of Foes''. Ironically, although it has returned to being an omnipresent aspect of the Multiverse, in that there's always somebody fighting the Blood War somewhere, it's even more downplayed than in 4th edition; it's primarily restricted to the [[Abyss]], to [[Baator]] and to the [[Prime Material]], and whilst important, it's not the Sole Important Conflict like it could feel in AD&D. Furthermore, it's even ''more'' simplified in terms of its conflict, being literally a combination of tradition and viewpoints; both demons and devils want to conquer the multiverse, but the anarchistic arrogance of the demons and the elitist, hierarchy-obsessed mentality of the devils means they can't get along.

Also, it's theorized that the demons may actually have hit upon a perfect plan; concentrating on destroying the Nine Hells means they have a singular target to focus their collective rage against (which keeps them all flowing in roughly the same direction) '''and''' it keeps the Forces of Good off their back, because they're content to let evil destroy itself - if they did go after other targets, they'd lose what little cohesion their hordes have ''and'' would become a big target for devils and [[angel]]s alike. Far smarter, in their opinion, to beat the devils first, and then look to the next major enemy.

The most unique addition to the lore in this edition is the idea of Balance, a group of cosmologically aware individuals who are so afraid of what might happen if the Blood War is brought to an end, even by the destruction of one fiendish race entirely, that they deliberately do whatever it takes to ensure that eternal stalemate. This is stated on the Tome to be [[Mordenkainen]]'s goal, which means it lines up uncomfortably well with his reputation as a [[Stupid Neutral]] character - the book even nods to just how much hatred members of The Balance bring on themselves, and admits that some of its proponents are really using it as justification to pursue their own ambitions or power-hungry goals.

In the "Paradise Lost"-esque section, ''The Trial of Asmodeus'', the titular character uses the Blood War as a defense, saying, essentially, "all lawful planes would be fucked if I wasn't there to beat back the demonic hordes!"

Interestingly enough, the books of the 5e setting make it very clear that the Blood War can actually have wildly differing states from time to time.  If the PCs in ''Descent Into Avernus'' succeed in rescuing all of the NPCs they can, kill or redeem every named devil, etc, they can give the demons such a huge boost thanks to removing most of their opposition that the Blood War can push all the way down to the lower levels of the Nine Hells, which the book explicitly notes hasn't happened at any point in cosmic-level timescales.  Of course, that isn't true, thanks to 4e, but it's still notable as an instance where the book itself calls out how a mid-level party can seriously overhaul an entire plane of existence like that.  It also helps to highlight how badly overmatched Demon Lords are against even the lowest-ranked Archdevils.  Zariel and Bel are the weakest Archdevils and they can kick the living Christ out of Yeenoghu and Baphomet and even Orcus if you go by RAW.