ShadowClan

ShadowClan is a group of cats that live in the marshlands and pines of the forest. They are one of five clans who live there.

The information below is from the official Warriors Wiki 

Description
They are proud, loyal, defensive, and slightly arrogant; often seem to be misunderstood and portrayed by the other Clans as battle-hungry, aggressive, ambitious, and greedy for more territory. It was often said when the Clans were in the forest, that the cold north wind of the mountains chilled the ShadowClan warriors' hearts. However, as Rock states in Cats of the Clans, ShadowClan has the smallest amount of territory and prey, which may justify their willingness to add anything to the fresh-kill pile. Even though their fierce warriors and hostile leaders earned ShadowClan its reputation, the leader Dawnstar led Firestar to believe ShadowClan was not always as unfair and cruel as they seem now. Their main prey is reptiles and amphibians, such as lizards and frogs. A secret food source is the carrionplace, though they are careful not to eat crow-food. They also hunt rats from this area when prey is scarce. ShadowClan cats hunt best at night and are better than others at sneaking through undergrowth. In battle, ShadowClan cats use shadows as an advantage to fighting.

Forest territories
The ShadowClan forest territory is located in an area that Twolegs have no specific name for. The territory also includes Twoleg places such as Windover Road, and the North Allerton Amenity Tip, and the North Allerton Road. Landmarks in this territory include: The forest is quite different on ShadowClan's side of the Thunderpath. Instead of thick trees, there are more pine needles. The camp is protected by brambles, and the entrance is through a tiny path. There is hardly any grass, but the ground is muddy and cool. The leader's den is beneath the roots of a big oak tree. The warriors' den is under a bramble bush. The den looks prickly on the outside, but on the inside, it is lined with pine needles and moss. There is a smooth boulder at the edge of the clearing, known as Clanrock, which serves as a higher place for the leader to address the camp. Propped up next to this large rock is another rock, and it creates a sheltered cave underneath. It is the medicine cat's den. Sick cats can rest in the ferns surrounding the boulder. There is another hollow shielded by a thorn bush. This is the nursery, and the thorn bush provides protection.
 * Camp - A dark, well-concealed hollow hidden deep in shadows. It is surrounded by prickly and fierce brambles.
 * Carrionplace - The cats' name for a landfill, an evil place where numerous rats and diseases lurk.
 * Thunderpath tunnel - ShadowClan cats move freely under the most feared part of the Thunderpath. This has enhanced their reputation for mysterious strength and invincibility. The tunnel goes into ThunderClan and WindClan territory.
 * Burnt sycamore - An ancient tree struck by lightning many moons ago. Apprentices are trained here to hunt at night and stalk through undergrowth.

Lake territories
The ShadowClan lake territory is located in an area that Twolegs call the Sadler Woods. The territory also includes Twoleg places such as the Hareview Campsite, the Sanctuary Cottage, and borders called Littlepine Road and the Littlepine Sailing Center. Landmarks in this territory include: The camp has a small pool nearby, so the cats don't have to go all the way to the bottom of the lake to fetch water for elders or the medicine cats. The actual camp is in a tangle of brambles, with low-hanging branches and boulders all around and above it. These brambles and branches help protect against badgers and other big creatures. Many trees surround the camp, enabling cats to climb up them and see the activities of the Twolegs on water. From these trees, the cats can see all the Twolegs and their water-monsters in the water. The entrance of the camp is through a thorn tunnel, and brambles. At the camp entrance is a large boulder, which cats have to slip past to enter the camp clearing.In the middle of the clearing grow ferns. There is a clear progression of dens from one side of the clearing to the other which are all in bramble thickets. The nursery is first, then the apprentices, then warriors, then the leader, and finally the elders at the end of the circle. This structure enables the kits and elders closest to the low-hanging branches and the warriors facing the entrance, if any kind of trouble. The medicine den is in a far corner, beyond the leader's den. It is a sandy, hollowed-out floor covered in dried pine needles. There, the branches are not so bunched together, letting the medicine cats examine the skies for omens. Above the leader's den, there is a hazel branch that hangs over. This serves as a kind of vantage point for the leader to address their Clan.
 * Camp - Closer to Twolegs than in the old forest territory, but it is well hidden and difficult for attacking enemies.
 * Twoleg nest - Home to two aggressive kittypets: Susan and Jacques. If they catch Clan cats out alone, they attack immediately.
 * Twoleg path - During greenleaf, Twolegs tramp along these paths all season.
 * Greenleaf Twolegplace - Another place Twolegs inhabit during greenleaf. The Twolegs put up small dens and light terrifying fires. However, they also leave behind food much like the food found at the old Carrionplace.[12]