6. Possession opens pathways and is the best option for escape (and back kills).
The first level of possession allows Corvo to possess animals, particularly rats, fish, and hounds. That might not seem like much, but it gives Corvo a wealth of options for infiltration and escape. Only rats have access to rat tunnels and only fish have access to waterways and can fit through cracks in water gates. So if you can’t seem to unlock a door, Possession can easily be the key. It can also let you get around the front entrance of a building which might be fortified to a point where a frontal assault is not a sound strategy, even if you’re going down the lethal route.
At the second level, Corvo can possess human targets which is a powerful tool for both lethal and nonlethal playthroughs. If you’re playing non-lethally, the most annoying foes are Tallboys since they are immune to sleep darts and have a long range of vision. However, possessing them and walking them away to a safe distance away from wherever you need to go is a viable solution. Also, immediately following a human possession (which lasts about ten seconds), the target is rendered helpless with his back turned, allowing Corvo to dispatch him any way he sees fit and well away from prying eyes.
7. Kill every river krust.
River krusts, giant oysters that spew globs of acid (sorry, couldn't find a pic of it), appear at around the second half of the game. Most of the time, their shells are shut tight, but if Corvo gets too close, they will start opening and attacking. Of course, that’s when they are the most vulnerable, particularly to crossbows and grenades.
The best part is that most river krusts carry a pearl worth either 25 or 50 coins a pop. This is particularly good for non-lethal playthroughs, since Corvo will likely have more bolts and grenades than he can handle and killing krusts don’t count against the “don’t kill anyone” objective. They’re nasty, anyway. You might as well rid as many as you can off the face of Dunwall.
8. Pickpocket aristocrats (and, well, everyone).
Pickpocketing isn’t that difficult in Dishonored. All it takes is some sneaking around when no one’s looking to pilfer some coins or key. Sometimes, you can even crouch when a lot of people are looking, quickly steal a pouch, and then stand up, with the only punishment being a strong talking-to. Oh my...
Aristocrats unsurprisingly have a ridiculous amount of coin on themselves, and one particular segment in the game has Corvo meet many aristocrats in one setting (we’re being vague in case of spoilers). It’s like a thief’s paradise. There are at least 4000 coins floating around in that segment alone, all of which can be turned into many, many upgrades at Piero’s Workshop.
9. Fun with rats!
If you’re going down the path of high Chaos and bloody assassinations, why not have fun with rats? Summoning rat swarms easily distracts guards in their tracks and gobbles up their corpses. If there are still some guards remaining and you need to escape, possessing one and scurrying away is a sound method. Just make sure you don’t get stomped on.
Or why not try attaching a springrazor trap on a rat and then possessing that rat straight into a troop of guards. Bloody guts for everyone, and you stay undetected!
10. Use height or pistols to take down Tallboys.
While there aren’t any bosses in Dishonored, Tallboys will be the most difficult enemy you encounter in Dunwall. Taking down these towering pests can be downright tricky. If you’re going down the non-lethal route, the only way to get around them is careful stealth or human possession. If you're not, though, then they've got something else coming.
The easiest approach is to use Corvo’s upgraded pistol and explosive rounds upgrade, then place a well-timed shot right to the container of Whale Oil powering each Tallboy, which resides on their backside. Staying hidden will help your cause, as will using Blink to get behind them right around the same height as the Whale Oil tank.
If you haven’t yet upgraded your pistol, or perhaps you just want to save on ammo, you can use Blink to easily take out a Tallboy lethally. Get to a platform just above a Tallboy’s head, and perform a Drop Assassination. That’ll cut ‘em down to size.