At the start of this Quest, you will be tasked with scanning a new, specially marked set of drones. The strange drones only appear on the Grineer Sealab tileset. This includes any most Missions that take place on Uranus itself, but does NOT include spaceborne Archwing Missions (such as Caelus) or Missions on Grineer ships (such as Ur and Assur).
Remember that you can always buy more Codex Scanners from the Market if you run out!
During the final Defense Mission, the objective you need to protect will change locations every few moments. You will need to move quickly between the different targets to keep them safe and finally finish Natah.
The next Main Story Quest, The Second Dream, becomes available after completing the Neptune Junction on Uranus. Doing so, and defeating the Specter inside the Junction, will permanently unlock the world of Neptune and its Mission nodes for play.