Vandalized Achievement in Halo: The Master Chief Collection

This Easter Egg can be found in NMPD HQ. 

At the start of the mission, proceed through the doors with Buck and into the first rooftop section. If you’re playing on a lower difficulty setting, which is advised, simply run past all the enemies in this area and make your way to the doors on the far end of the rooftop. Move through these doors, climbing the stairs on your right so that you’re on a small balcony. Continue moving forward until you reach the end of the balcony. 

At this point, turn your character 180 degrees, then jump backwards off the balcony. As you are falling you should see a hand-drawn face on the side of the building you were just standing on. All it takes is looking at the drawn face for about one second and the achievement should unlock right away. If this text sounds a little too confusing, please refer to the video guide below for a visual representation of how this can be achieved. Please take note that this cannot be done in Co-Op play.