Use the following trick to easily liberate outposts without being detected. When you find an outpost that has a caged animal (for example, a bear or tiger), find a good hiding location inside the outpost with a good view of the cage, but far from it. Shoot any weapon with a suppressor at the cage. Make sure no guards are close to you when you shoot. Eventually the door to the cage will break open, and the animal inside will leave. All the guards and guard dogs will turn their attention to that animal. The freed animal will then "liberate" the outpost for you. All you have to do is remain hidden until all the enemies are dead. Doing this twice will allow you to to unlock the Ninja Step skill, which makes you very silent. It is also recommended to scan the entire area with your camera first so you can see the progress of the animal when you free it.