Well, in the lower planes, that gate is the River Styx. I mentioned they could just walk from one place to another if someone built a gate that stayed open. But they don't have anywhere near the same flexibility that other planar creatures have to travel, with one exception. Now, if someone was to foolishly just build a gateway that was open, they could just walk through. They need someone outside of the Abyss or the Nine Hells to call them forth. And then, we also have the further complication that demons and devils, unlike other planar creatures, don't have the freedom to use magic to just teleport or gate themselves from Hell to anywhere else. The demons just want to tear apart Hell and claim it as their hunting ground. the devils would love to control the demons if they could. Now, they definitely don't.Īnd then, you have law and chaos, which are very much. So maybe at one point they worked together. They share something, so maybe they'd come together.' But no, one of the key traits of evil is this sense that I come first, and so it's very hard for evil factions to work together, at least for a long period of time. Now, you'd think, 'Hey, they're both evil. demons are Chaotic Evil, and devils are Lawful Evil. Mike Mearls: So the Blood War is probably the most ancient of all the struggles, the conflicts that this book talks about that we see in Mordenkainen's Tome of Foes. And oddly enough, this war may be keeping many alive in the D&D multiverse. That brings us to the Blood War, the conflict, the fight between devils and demons.

Todd Kenreck: In Mordenkainen's Tome of Foes, there are a lot of adversaries, and some of them are not from the prime material plane.

The blood of war