The Coin's Fault

The Coin's Fault is an achievement in Halo: The Master Chief Collection. It is awarded for activating the secret Cortana Terminal on Cortana. The achievement is worth 5 Gamerscore and can be unlocked on any difficulty. Unlike the other Halo 3 terminals, this terminal activates a Cortana moment rather than text documents.

Location
The Cortana terminal is located in the basement of the room which contains the Tilt skull, where the gravity hammer is found.