Forerunner fleet

The Forerunner Navy is a branch of the Forerunner Armed Forces. It is led by Forerunner Fleet Command and is in charge of all space combat and naval operations. They held the responsibility of protecting Forerunner planets from space from the Flood in the Forerunner-Flood War.

Units
The last known actions of the Suppression, Security, and Emergency Circumstance Fleets were in an engagement against Flood controlled fleets in a last stand during the Battle of the Maginot Sphere
 * Primary Pioneer Group
 * Advance Survey Team Alpha
 * Suppression Fleet
 * Security Fleet
 * Emergency Circumstance Fleet

Ship Types

 * Dreadnought or Keyships and other forms of vessels, such as cruisers.

Known Units

 * The Forerunner Dreadnought, which was activated in Halo: Contact Harvest.
 * An unidentified fleet of ships of an unknown type hidden within the Shield World of Halo Wars.