Hello there, Thank you very much for reaching out to us. I'm sorry to hear that you are having issues accessing the Glory Beyond mission after completing the campaign. You can replay the mission by going to Potal > Renegades > Tharsis Outpost > Standard Expansion (it's the Renegades symbol on the left). From there, you can choose Customize and select the mission you want to play. There are two entries per mission: one is Brave, the other is Legendary. The -20 power delta is the Legendary variants.