The Fall of a Dynasty - Bonus Objective?

[Lord Margrave]

I have run this mission four times and the bonus objective refuses to complete even after I capture the rig. can anyone provide help on this achievement?

[Syncourt]

It completed for me even though the UI said that it wasn't completed.

[Vodka]

Captured all the rigs i could find. Didnt get any notifications during the mission itself. But it was marked as complete on the results screen and i did get the achievement.

[Selphea]

Afaik it's a specific rig all the way on the left side of the map. You know it's completed when they paradrop some vehicles on you as a reward. If it's not registering take a screenshot and submit a bug report.

[Lord Margrave]

Thank you all, the only thing I needed to do different was leave it where it was and keep it alive until the end of the mission. I kept moving it to protect the rig and that seemed to invalidate the achievement.