Hey Gamers! Welcome to Awakening the Nightmare DLC in Halo Wars 2!
This video will cover the 4th mission (The Archive) on Legendary difficulty while obtaining all optional/bonus objections, getting gold medal, all pheonix logs, and obtaining two miscellaneous achievements as well (We Got This and Nimble, for a big fella). This particular achievement does not need to be done on legendary difficulty, but this guide is designed to minimize playthroughs and show you how to obtain all achievements in one run.
I hope you find the video helpful!
-Damron Out