This zone starts with entrance area from the main map, called Strange Clearing. You will need to clear the boss, Mindwall to unlock the entrances to the other four areas, which are at the edges of the map - north, south, east and west.
Each of the four zones are Internment Camp for a particular pride. The Orcs in those zones will be themed to the pride (wyrmic, mage, melee...), and will initially be hostile. There will also be Ogres. In order to free to orcs (and make them non-hostile) you will need to locate the Mindcontrol Pillar in the zone and destroy it. The pillar is usually on the extreme edge of the map.
There is an achievement for finishing all the zones without killing any Orcs.