Weird War recs?

I'm in the mood for something supernatural horror & war related and hoping the sub can help me out.

I'm not looking for real-world, realistic, just ordinary war is hell or the horrors of war novels. I'm also not looking for pure alternate history novels. I have plenty of both, thanks. Also, while I love me some dieselpunk, unless it has supernatural-horror elements, it's not really what I'm looking for right now.

What I am looking for is supernatural horror & war novels. Vampires, werewolves, zombies, demons, occult, mad science, etc. Any or all.

My preference is WW1 and WW2, but I'll take just about any war as the backdrop.

I’m also looking for novellas or short novels rather than short stories or massive doorstoppers.

But, above all, it needs to be fast paced. For me, plot is way…way…way…more important than character. I regularly DNF books because of slow pacing.

Any recs that even ballpark what I'm looking for would be welcome.