“An Echo of Oryx has emerged from the rupture. Kill it!”
An Echo of Oryx will emerge from the Rupture just a short while after you attempt to enter it. You must defeat this Echo of the Taken King once again. There is a lot of cover that can be found through the area. The problem is there are more enemies around. Likely though they are occupied surviving the other threats aside from the Guardian.
Throughout the fight, the Echo of Oryx will use Grasp of the King. This debuff will drain your Super meter. The Echo uses it enough it is very difficult to complete charge and use your Super in this fight.
It will also summon in a high number of Taken Hive. Be on guard for them and eliminate them all very quickly. Remember to aim for their glowing eye to quickly eliminate them. The same can be said of the Echo of Oyrx as well. Be very aggressive and you should have little trouble with this fight. Winning the fight will end the mission.