From Halopedia, the Halo wiki
Labyrinth is a large 2v2 map, with building sites situated at regular intervals in the map. Large Forerunner walls also take up parts of this map. The areas of building sites slightly resembles a grid, with sites in some squares. The centre path of the map provides a direct route from one side of the map to the other. A beam emitter similar to the ones found on Installation 04 could be found in a corner of the map.
A feature unique to this map is the Protector Sentinels, which can be purchased by players at the protector plant and attached to squads. There are three unique variants, which can attack enemies, heal units and project protective shields. The map also features several Forerunner forts, which take the place of empty base build sites. These bases are protected by powerful Aggressor Sentinels, Super Sentinels, and beam turrets. With Sentinels being air units, these bases are a bit more difficult to assault early on.