A great game that I consider a hidden gem that btw I reviewed recently. Dishonored can be somewhat linear but you will see that as you progress through each mission you will find thousands of ways of how to do things and even more will emerge. I recommend boosting your skills as much as you can and if you want to be non-lethal (recommended), it means not kill too many guards, the X-bow with numbing darts is a good option. Good luck with the adventure in Dunwall city and have fun :)