Za'zayara-pattern Harvester
From Halopedia, the Halo wiki
The Harvester is a Covenant machine used to take materials from a planets surface, in order to later turn it into fuel for cruisers or other vessels. Generally used in long-term invasions Harvesters are not commonly seen by UNSC personnel. Harvesters are normally run by Drones or Yanme'e and are a "hive" for the Drones, with a functioning colony within.
