Key To Pirth

Key To Pirth is an Achievement in Halo Wars that is worth 50 Gamerscore. It is obtained for beating Act 2 on any difficulty. Act 2 consists of the missions Arcadia City, Arcadia Outskirts, Dome of Light and Scarab.

Trivia

 * The name is a reference to Pirth, the capital city of Arcadia, as all the levels in Act 2 take place on the planet.
 * The name is also likely a reference to the custom of giving a key to the city to someone, usually a hero. In this case, its likely supposed to be a reference to the crew and the player saving Pirth and Arcadia from the Covenant invasion.