Cortana, UNSC Artificial Intelligence (SN: CTN 0452-9), is a smart artificial intelligence construct. She serves as the A.I for the UNSC Pillar of Autumn and partner of John-117.

Overview & Background

Cortana is the highly advanced A.I. at the heart of the Pillar of Autumn. Her design allows her to be uploaded into an appropriately configured battle suit for increased mobility. She is capable of hacking into alien computer systems, and has used this skill to intercept Covenant communications during combat. She interprets this data to provide her caretakers with directional waypoints and the best available information about troop movement and strategy.




Despite being an A.I, Cortana is known for having a smug, yet caring attitude. She is also known to be very curious on learning about Forerunner architecture, just like her creator, Dr. Halsey.

Her relationship with the Master Chief is very friendly, yet different since John-117 is the one that shoots and she is the brains.

Developer Informations



  • Her design closely resembles how she appeared in Halo 4.
  • In the cryo area of the Pillar of Autumn when visited in the early parts of The Maw, players can inspect one of the panels in the upper control room to find the Cortana log, written by Cortana herself. There is only this one in the field in the whole game, but the content changes depending on the difficulty setting being played. This means that there are a total of 4 Cortana logs that are all found in the same place, but only one can be viewed in any one playthrough of the level.



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