As soon as we dock at Greystone, you’ll see the restricted area on the map. As per usual, as soon as we enter we’re going to be treated as hostile. So stealth is in order, well you don’t need it – it just makes things a whole lot easier!
First, we’ll go for the powder reserve that we need to destroy and to do that, we simply need to continue heading east from the end of the dock, being sure to stay out of sight and using rooftops or stalking zones of course! You’ll arrive at an open shelter with the barrels inside just opposite the tavern icon. Shoot this to complete your first objective.
Return back towards the dock a short way and enter the area around the open boat building setup in the centre of the zone. The guard captain wanders around here, so find your way into the stalking zones around the outside of the central structure and use eagle vision to locate him. Once you have spotted him, wait for an opportune time to strike and then take him down (I whistled hi into a stalking zone, but feel free to do your own thing!). Be sure to exterminate or escape any nearby guards that spot you and become anonymous before pressing on to the final objective.
Finally, we need to light a signal tower. There is a large brazier located at the top of a ladder on the southern section of the map close to the water. All we need to do now is interact with this whilst anonymous to end the settlement takeover.