Part 617

From the Fusebox, sneak to the barrels by the stairs to grab the Crowbar.

Sneak up the stairs to the Tower Storage room and enter it.

Grab the Bag of Gunpowder and go to the top of the stairs.

Wait for the patrolling Guard to stop just outside the door, then exit, subdue him, and pick up his weapon.

Drag the subdued Guard just inside the room. Wait for The Constant to go into the Library.

Go to the corner closest to the standing Guard. When he is looking forward, place the weapon you just picked up at the corner.

When he looks right, he should see the weapon and go for it. Grab him when he gets close, pick up both weapons, and drag him to the other Guard.

Go to the door for the Hyperborea Showroom floor, climb the railing to the left, and shimmy left to the Pipe.

Go to the Ledge to the left of the Pipe, climb it, and walk it all the way around the corner to the patio outside the east side of the Architects' Lounge. The Constant should be back inside the castle by now.

Unlock the door, and quickly step right when it opens to get out of view.

Place a Coin in the corner near the door, take cover (press the cover button to crouch behind walls or objects) to the right of the door, and wait.

When Sophia returns, her Guard will stand by the door. Open the door and toss a Coin towards the other Coin to lure him, then run behind the boxes.

When the door closes, get up behind the Guard as he picks up the Coins, knock him out, and drag him behind the boxes to hide him. Pick up the Coins and his weapon.

Go back along the Ledge and to the bridge.

Go inside the Hyperborea Showroom floor and turn right to enter the Storeroom.

Go to the chair at the end by the door and place your three Coins on the floor by it.

Open the door, stand near the Container, and toss the Bag of Gunpowder at the Coins. An Ark Member near the Study's door should be lured by the noise.

Go back a bit more, bring out the Crowbar, and wait.

When the Ark Member walks in, they should see the Coins and come closer. When the door closes, stun them, grab the Bag and Crowbar, and hide them in the Container. Repeat with the other Ark Member to clear the way.

Pick up all objects and enter the Study. Crouch by the Radio and wait.

The top of the Gallery Stairway is on the opposite side of the wall. When Sophia arrives, turn on the Radio to lure her inside.

Go to the north end of the nearby couch and take cover. When she gets to the Radio, get up behind her.

The moment she turns it off, knock her out and drag her to the Container. Shoot her in the head to kill her and dump her in the Container.

Run back to the Storeroom, then go back to the bridge for the Library. Climb over the railing again and to the Pipe.

Slide down the Pipe all the way to ground level.

Re-trace your steps back down to the ladder for the East Wall. Climb down when the Guards aren't looking.

Sneak to the exit point when it is safe to do so to leave the mission.