- In each level, you can obtain a medal for a]not being detected, b]killing everything, c]not killing anyone. Those are just for score purposes and only unlock skins that do not affect gameplay.
- Scrolls scattered over the levels, on the other hand, give you skill points. There are exactly enough scrolls to unlock every skill so it might be worth replaying stages to find them.
- If you're going nonlethal, most of your arsenal is self-explanatory; go for invisiblity and decoy first, detecting guards through walls and the blinding wave are situational.
- If you're going to kill stuff, you have a bit more choice with your tools. Unlock disposing of bodies ASAP, then it is mostly up to you: hands down the best kill skill is Shinen, which places a black hole trap capable of killing multiple guards and removing their bodies. Kunai looks great on paper especially when archers start showing up, but it is loud and it leaves a corpse; furthermore even archers on overlook positions are usually in some wandering guard's field of vision so most situations where it would come in handy only result in an alarm.
- If you're killing and using techniques a lot, make unlocking Shadow Kill a priority: the ammo-refilling shrines are few and far between and this way you can keep yourself well-stocked in traps and daggers. Non-lethal players are, sadly, screwed.
- The ledge kill skill has another use the game does not tell you about : it also works with ceilings which makes the indoor sections considerably easier.
- Your primary means of movement should always be the shadow dash. The fact you are able to cover distances instantenously and without being seen is a fantastic tool with distractions and traps - if you're faced with a complicated guard pattern, just find a shadow in the middle, ring your chimes and teleport behind them before they even come to investigate. If you're feeling particularly nasty, leave a Shinen as a present...
- When you don't see a way past a situation, look up. Even flat areas usually have some arches or roofs you can use to get to the other side.
- While one hit from anything kills you and every enemy has a ranged weapon, all is not lost when you're spotted. You can often shadow dash out of the way or behind the enemy and slit his throat before he calls the alarm.