You'll want to take your time with this one since getting spotted means trouble. Follow those mMonolithian patrol routes first, and use the steel scaffolding for cover while they do their rounds. Most guards have specific patterns so watch them do a full cycle before moving. The surgical room with the regenerator is your main target, but getting there needs patience. When you're creeping around, the ventilation shafts are your best friend, especially when the main paths get dicey. Staying in the dark helps a ton, and if someone spots you just backtrack to the nearest vent instead of fighting. Really cool thing to know, keeping everyone alive gets you bonus coupons from the doctor. Save your sprint energy for that nasty electrical anomaly near the end, and remember the guards sometimes stop to pray which is perfect for sneaking past. The display case with the device isn't too hard to reach once you've got the timing down, just make sure you're moving when the guards are facing away or distracted.