shields can block almost any damage. if your shield get hit you will lose stamina. how more powerful the hit how more stamina you lose. the shield will block a part of your view and if you go to blocking mode you will see almost nothing.
stealth mode can be used to kill people without them alarming other people. in stealth mode you make less noise but move slower. you can grab someone in stealth mode,you need to mash space bar as quick as you can and use the attack button to damage him until he’s dead. but the guy you grabbed can do a similar thing. if he mashes space bar faster than you he will escape. also the grabber will have a disadvantage because(for example) every 5 times you hit the space bar just 3 of them count. this way it is very hard to keep someone grabbed but you will do a lot of damage before he will escape