Keeping the Mood During Combats?

[wertyou2]

I was just wondering if anyone had any tips for keeping the general feeling of horror and despair during the combats. Right now we're in Fort Hailcourse (which admittedly isn't too terrifying of a place, except perhaps Clyme's body), and the creepy atmosphere that was going so well during the exploration of Thrushmoor is starting to fall away due to the combat after combat nature of dungeons. Does anyone have any suggestions for keeping things scary while still being able to focus on running the combat and keeping things chugging along at a reasonable pace?

[Spastic Puma]

I decreased the number of encounters and smushed them together/rearranged them to make it less repetitive/predictable. One thing I found was effective was making some encounters a bit over-the-top CR-wise but giving the players a way or two to avoid that fight through stealth, puzzles, diplomacy etc. That way they don't get the impression that everything they meet is easily dealt with by just clubbing it over the head.