The Key achievement in Halo: The Master Chief Collection

The Key

Halo 3: Complete Cortana.

The Key-0.1
1 guideOnline/OfflineSingle PlayerCooperativeMain Storyline

How to unlock the The Key achievement

  • Apache117XApache117X731,191
    13 Feb 2015 07 Feb 2018 07 Feb 2018
    6 0 0
    This is a campaign related mission for MCC: Halo 3.

    To obtain this you must finish the mission Cortana. Mission difficulty doesn't matter.

    However, you must be carful if using skulls as some may void the achievement, these skills have a warning on them before you start the mission (anything with a 0.00 multiplier).
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