Feet First

Feet First is an achievement in Halo: The Master Chief Collection. It is unlocked by completing all Spartan Ops chapters. The achievement is worth 10 Gamerscore and can be unlocked on any difficulty.

Trivia
The Master Chief Collection features achievements for completing each campaign on Easy difficulty. As the game features achievements for completing Spartan Ops on every other difficulty, this achievement functionally serves as the Easy difficulty achievement.