If you are looking to go the Low Chaos route in Dishonored 2, one of the trophies/achievements you will want to nab is called Ghostly. In order to unlock this, you will need to beat an entire mission without alerting anyone to your presence. This is easier than it sounds as enemies can quickly spot you in Dishonored 2 if you are caught out in the open for more than a second, so knowing the best route is the key to victory.
Ghostly is easiest to unlock during the first mission as many of the guards have very predetermined routes. and interactions with civilians are great distractions. Once the level loads up, turn around, unlock the window, and go outside on the ledge until you can enter through the next window on your right. Slip back inside and speak with one of your fallen comrades before she dies. Quickly go into stealth mode and move to the door on your right near the beginning of the hallway.
There will be two guards there. Wait till they split up and knock the first one out upstairs, making sure to take the bedroom key off of him. Move his body into the study where you started and then head down the staircase, knock the other guard out and hide his body in the same place. After this, you will need to go back downstairs and open the two glass doors which will trigger the A.I. to begin talking with each other. Your target will be heading back upstairs so go hide in the study with your unconscious friends and wait.
You can either look through the keyhole or follow the giant marker over his head to determine when he is upstairs and has his back to you. Either kill or incapacitate him, reclaim your ring and head into the safe room. Gather your gear and head out to Dunwall, making sure to snag the painting on your right of the Pendleton brothers. Move across the rooftops until you reach a balcony that overlooks a soldier just relaxing below you. Either drop assassinate/takedown this man and move on top of the checkpoint’s roof just behind where four guards are speaking.
Wait for them to break up and hop down off the roof, quickly moving to the only guard remaining with his back turned to you. If you’re fast enough you’ll be able to grab him and stash him in the checkpoint before anyone sees. By the time you are done, two of the guards will have walked up to where the first one originally was, so take your time and take them out silently. After they are disposed of, head down the road towards the city streets and quickly jump down onto the lower level to your left. Follow this path to the end, making sure to time your movements right so the guard at the end of the road doesn’t spot you.
Repeat this same idea (only this time the lower area is on the right), until you reach an open area with several dead bodies scattered about. Move from cover to cover as you cross the street and jump over the railing. You will land on some rocks which you can follow down to the ocean without having to deal with the soldiers at the docks. Swim towards the boat, talk to the captain, and once the mission ends the Ghostly trophy/achievement will be unlocked.
One of the biggest tips for trying to sneak through Dishonored 2 is to frequently save since you may get spotted once or twice. If you alert a guard, just reload the save and try again until you make it to the very end. This is very much about trial and error, but it is by far the easiest level to unlock this on. Happy hunting.
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