Unity Be My Guide
Very rare1.5%ObjectiveOptionalAnywhere
Spend 20+ Unity Points in a single game.
The Unity mechanic is unique to the Advent factions - i.e. you must play as one of the two Advent factions. See the linked guide page for more about Unity, how to get it, and what it can be used for. For this achievement just spend at least 20 points in a match.