Do You Remember When We Met Achievement in Halo: The Master Chief Collection

As a means of celebrating the launch date of the original Halo 3: ODST, this achievement simply tasks you to play the aforementioned game on the 22nd of any month. This can be done by playing any of the Campaign missions, be it the Mombasa Streets or NMPD HQ. Overall, this achievement is pretty straightforward and can be obtained with minimal effort of your part.