sneak behind someone and shoot him in the butt,if done right he will sometimes jump up grabing his butt and occasionaly go into a dance.
First go into a level with scientists.select secret agent or higher,then go up to a scientist and shoot him in a limb twice.Then he will pull out a dd44 on you and eventually throw a granade.
If you have ivincibility go to silo,plant a plastque and shoot it.Then walk around and you'll see all the people die.
If you have fast animation go to jungle and let natalia shoot most of the people pretty soon she will run out and just sit and aim at the person she just shot
Go to facility and go to the vent opening but don't go down.Now turn to the vent plate to the left of the opening.Now shoot the bottom part of it.if you go down and look at the ceiling.there should be bullet holes.