"All of creation cares not whether you live or die."
Shadow War is the dark side of War and serves as a Boss in Darksiders. War needs to defeat his dark side in order to enter Eden and visit the Tree of Knowledge. Shadow War can morph into Chaos Form and he has the same attacks as War.
This fight is fairly easy, even on Apocalyptic. You fight Shadow War in Eden after the fight with Straga and obtaining the Mask of Shadows. After activating the Mask of Shadows, Shadow War suddenly appears in front of War and the battle is joined.
Shadow War loves to block your attacks and then try to counter you with a vertical mid-air spin attack (which is in fact War's own Flipsaw attack). Shadow War also uses a two-hit slash with his own Chaoseater and also uses one of War's wrath abilities, the Blade Geyser. Shadow War also knows how to dodge your attacks by moving sideways just as you are fixing to slash him with your Chaoseater and then counter with his vertical mid-air spin attack. Don't be alarmed, Shadow War doesn't know ALL of War's moves, but only a set amount. Also, Shadow War's only weapon is his own Chaoseater so he doesn't have a Tremor Gauntlet nor a Scythe.
As the fight progresses, Shadow War eventually turns into his own Chaos Form. That's your cue to also turn into Chaos Form. The rest of the battle should be easy and you should win the battle before your Chaos Meter runs out next to your health bar. (You can defeat Shadow War without using Chaos Form, but it takes a lot longer.)
Completing the battle triggers a cutscene in where War's regular form and Shadow War's Chaos Form punch each other and collide fists but War's strength is more powerful than his shadow counterpart and War punches Shadow War turning him back into his regular form. Shadow War being on his knees gets a short glimpse from War only to be decapitated the next second.
- Shadow War only appears before War when he first uses the Mask of Shadows.
- Shadow War is already equipped with the Abyssal Armor and, as he is the dark side of War, also the Chaoseater.