The route I chose to take to the watch tower was through a shutter opening at the back of Dr. Hypatai’s lab. I used chloroform, that you can from top of the stairs just before the entrance to the lab,

to knock out the 2 guards that were on the deck outside below the shutter opening.

I did this by first distracting the guard with and empty bottle so they move closer to each other and then throwing a chloroform bottle down. Before distracting the guards I had to wait until the elite guard moved away from the edge of the wooden loading platform, otherwise he’ll get spooked and fall off the edge and most likely die, and that’s not good if you don’t want any kills on you play through.

With the guards out of the way I could jump onto the light tower and disable it

With the light tower out of commission all that remained was to meet Meagan Foster down at the dock. There is one more guard one level up from dock level but I was able to just sneak around him unnoticed.
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