Follow your objectives until you reach a familiar-looking grove with a wonderful view of Lua. You can take out your Codex Scanner here to begin searching for orange, scannable objects to proceed. There are four in total across the area marked by a yellow circle on your map.
Your next Mission sports a new obstacle: doors locked behind Orokin Memory Ciphers. You need to find symbols scattered around the environment before entering them into a combination lock.
Luckily, the correct combination to unlock each door will be displayed above the cipher after you find each set of symbols. Just make sure to actually find them all within the yellow circle marked on your map! The lock will not open unless you actually find them first (no cheating with trial and error allowed).
Once you finish your search, you’ll return to the Orbiter to build a unique new Warframe: Excalibur Umbra. The process only takes a few seconds and will immediately trigger the next stage of your Quest.
Similar to past story-driven Quests, there are a number of important revelations and climactic battles from this point onward that we don’t want to spoil. When the dust settles, however, you’ll retain Excalibur Umbra as your reward!
The four scannable items on Earth include the sword next to the large tree at the center of the grove, a helmet by a large stone down some weathered steps leading down from the sword, debris in the grass near the waterfalls by the entrance and some fabric hanging from the stone pillar topped by a large tree root.
You cannot brute force the Orokin Memory Cipher puzzles. The correct solution will only work after you find all of the symbols scattered throughout a given area (no cheating with trial and error allowed).
You may wish to craft a new Amp by speaking to Onkko in Cetus or Little Duck in Fortuna before taking on this Quest. These NPCs will sell you Amp parts in exchange for Standing you can earn by hunting Eidolons or the Profit-Taker Orb in special open-world battles. Each new Amp requires a Prism, Scaffold, and a Brace to construct but you can mix and match to create your own custom design! This upgraded Weapon will be quite useful on the journey ahead.