With all of the guards around overseer headquarters out of commission I wanted to back track to go and visit the shrine. There are a few ways to get there depending on if you are doing a stealth play through or not. For the stealth strategy and no loss of health I went to the crane just past the overseer building. There is a chain that you can climb down and then swim around to another crane and climb up and you will be on the other side of the wall of light.
The shrine is on the second floor so I reach over to the second balcony and once inside there was an overseer looking for a book so that allowed me to render him unconscious. The second overseer was at the top of the stairs talking with the cleaner I think so I planted a stun grenade behind him and when he was done talking he walked right into it and he was incapacitated. With the shrine done I moved outside to start taking out the rest of the guards.
I waited till the guard sitting on the railing was finished talking with the guard at the wall of light and moved in and put him to sleep. I hid him up on the windmill platform and at the same time turned it off. Once the power was off the guards came to investigate so I hid until they went back down.
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