Rising Tide is a Quest released in Update 26.1 (2019-11-22), which tasks the player with collecting the parts they need to construct a Railjack.
Walkthrough
In order to access this quest, the player must have first completed The Second Dream quest. Players must also have access to a Dry Dock facility in a Clan Dojo, thus players can only access this quest if they are in a Clan.
Upon satisfying these requirements, players can visit the Dry Dock to purchase the Railjack Cephalon blueprint from the Dry Dock's central console for 
35,000. Once players have completed the blueprint, they must return to the Dry Dock to fully reactivate the Cephalon, who introduces himself as Cephalon Cy, after which he will explain the importance of the Railjack in combating the Sentients.
Recover the Railjack's Fuselage: Ares, Mars
Enemy Level: 20 - 25
The player's first mission for Cephalon Cy is retrieving a derelict Railjack fuselage on Mars, where it is guarded by a contingent of Grineer. Players must plant a scanning beacon on the wreckage, which will trigger a mission to defend the wreckage as Cephalon Cy scans it. A white circular radius will indicate the defense area, and players must stay within the area while preventing enemies from stepping within it, otherwise the scanning progress cannot proceed.
During the scan a couple of Vomvalyst Interference Drones will show up that will interrupt the scan, requiring that players kill them to resume.
Once the scan is complete, players can head to extraction to finish the mission, which will reward a Fuselage component. With the Fuselage component in hand, players must head back to their Clan's Dry Dock to install the Fuselage, which will materialize the Railjack's incomplete main hull inside the Dry Dock.
Repair the Railjack Fuselage in the Dry Dock
In order to complete the repairs to the Fuselage, the player must collect various resources that can be found throughout the Origin System that will be used for the repairs. The following lists the resources needed to initiate repairs:
1,000,000 Credits- 3,000 Script error: The function "Resource" does not exist.
- 15,000 Script error: The function "Resource" does not exist.
- 30 Script error: The function "Resource" does not exist.
- 100 Script error: The function "Resource" does not exist.
The Cubic Diodes is a resource that can be dropped by any Eximus units located on the Grineer Shipyard Tileset on Ceres.
Players can deposit any of the required resources they have at hand on the central Dry Dock console similar to depositing resources for Clan Research. Once all the required resources have been deposited, Cephalon Cy will initiate repairs on the Fuselage, which will require 12 real-time hours to complete.
Recover the Railjack Propulsion System: Cervantes, Earth
Enemy level: 20-25
The player's mission is to recover the propulsion system from another derelict Railjack, this time on Earth. Just as before, it is guarded by Grineer enemies. The player must scan the wreckage and defend it from incoming Grineer trying to interrupt the process.
During the scan, two waves of Interference Drones will appear, one at 40% and the other at 60%.
Once the scan is complete, players can head to extraction to finish the mission and acquire the Propulsion component. It must be installed in the Clan Dojo's Dry Dock to progress the quest.
Repair the Railjack Propulsion System in the Dry Dock
Once more, the player must collect various resources to repair the engine. The following resources are needed:
- 1,000,000 Credits
- 60 Carbides
- 1,000 Cryotic
- 30 Orokin Cells
- 20,000 Nano Spores
The Carbides are a resource dropped by Eximus units located on the Corpus Ice Planet tileset on Europa .
