When you start the game, you only begin with one weapon slot and not much else besides. That’s where crafting comes in, but in order to get more things, you’ll have to hunt down the animals. Whenever you liberate Bell Towers, you will notice animal icons on your map, which will give you general locations of those animals. Note that it’s possible to encounter other animals in those regions.
New to the series is Bait, which you can get by killing and skinning animals. This is a throwable item that will usually attract the attention of predators, so it can be used to get an animal to spawn. However, Bait only seems to be able to attract certain animals, like leopards, tigers and bears.
Far Cry 4 also adds incentive to those that prefer to hunt animals with things like a bow or the knife, as it lets you get two skins. In addition to that, doing a "clean kill" will also net you a small amount of Karma. All animals that yield a skin/hide can be killed by normal guns, letting you get one skin/hide. However, killing an animal with flames or explosions will sometimes ruin the hide, meaning you won’t be able to use it to craft.
Each piece of equipment in the game have four tiers that you can upgrade, except for weapon slots, which only has three. The first three tiers will require normal animal hides, while the fourth tier will require one from a rare animal. These rare animals are connected to the Kyrat Fashion Week side missions.