Greased Lightning Achievement in Halo Infinite
Complete the Movement Yard in under 25 seconds.
This achievement is found in the tutorial. It requires you to run an obstacle course in under 25 seconds. There are some dummies you need to melee along the way but on your subsequent runs they will still be gone. So get rid of those and we can do a fresh run.
To restart you need to turn around from the ending, jump across back to where you came from and jump the wall back to the starting area.
From there you can restart the course by putting you AI in the door terminal.