No Stone Unturned Achievement
No Stone Unturned15
Complete 16 optional objectives.There are 16 optional objectives divided among the first 8 main campaign missions (Mission 9 does not have any optional objectives or collectibles). Refer to the individual mission completion achievements for a list of all optional objectives.
For completing all the objectives in a mission, you earn a star at the end. If you miss any, you can replay the mission at any time in an attempt to complete anything you missed. Any optional objectives, kill challenges or collectibles obtained in previous playthroughs will remain completed.
Optional objectives are shown on the map as you progress through the mission rather than being revealed from the start. They are discovered through intel and collecting classified documents (for Burn after reading (15G)). They are then shown on the map as a blue diamond. The list of objectives on the map is toggled by pressing .
For videos on how to complete each optional objective, as well as all collectibles and kill challenges, refer to THIS THREAD, courtesy of 360GameTV.
Note: As DLC missions are released, the requirements for this achievement will not change. If you complete any optional objectives in those DLC missions, they will count towards this achievement, so this may unlock earlier than expected.