Empyrean introduces ship-to-ship combat to Warframe. You need to build, then pilot, massive Railjack ships in missions against the Grineer battle fleet. You and your crew are taking on enemy fighters, boarding enemy ships, and completing tasks across the expanded Star Chart.
You will need to team up with other Tenno, and everyone will have work to do during these fights. You need to repel boarding parties, put out fires, make ammo, pilot the ship, and much more.
Before you can start Empyrean, you will need to do three things.
Once you do those, you can start the Empyrean content. First things first, you need to go to the back of your Railjack and interact with the Reliquary located in the aft. You will go on a mission to find the final piece of your Railjack.
This section is a short mission that takes place on Lua. Run to the waypoint, grab the item, and then make your way. If you are low level, watch out for Battalysts, but you only need to run to the extraction.
After that, return to the ship, go to the Reliquary, and place the item there. Now, prepare for some strong feels as your Railjack comes to life. After that, all you need to do is head to Navigation at the front of the ship.