Dirge of Madrigal Achievement in Halo: The Master Chief Collection

This Easter Egg can be found in the mission, The Covenant.

The hidden music cue in this game is none other than Dirge of Madrigal, a song that original Halo developer Bungie used in one of their previous video games. When standing in a specific spot on the aforementioned mission, you will be able to hear the faint melody to the song. Be sure to follow the guidelines listed below, since it’s a slightly complicated process to trigger the hidden music cue.

• After defeating the two Scarabs, ignore the waypoint and fly a Hornet toward the left of the Citadel (the building that Truth is located in)
• Carefully land the Hornet on the structure and run along this ledge
• Eventually, the ledge will turn into a 45-degree slope, but at the top of the slope, the song can be heard
• It will begin to play almost immediately after you reach the top of the slope

Overall, once you have successfully reached the required spot, Dirge of Madrigal will be triggered and the achievement will unlock.