Stolen Dreams

The Lotus learns that the Grineer have unearthed the last of the Arcane Codices in order to decipher their nature. The Grineer's plans are dashed however when Maroo, a professional thief, steals the last piece of the Arcane Codices and goes into hiding. Expressing an interest in the Codices, the Lotus sends the Tenno to find and capture Maroo, who was hiding in a Corpus base on Tharsis, Mars. She explains that  the Arcane Codices have been a mystery for decades since they were first unearthed, with no one knowing what they are.

After capture, the Tenno receive a video transmission of Maroo's interrogation, where she reveals that Tyl Regor had hired her to retrieve the Arcane Codex piece from an Orokin Derelict. Due to her dislike of the Grineer however, she gave the Grineer a fake, and sold the Arcane Codex to the Corpus. After being persuaded of the danger the Grineer pose to her, Maroo agrees to the Lotus' offer of protective custody in exchange for revealing the location of the Arcane Codex. With Maroo's info, the Arcane Codex piece in the Corpus' possession is found to be held in a Corpus Outpost on Unda, Venus. The Tenno are thus tasked with a Spy mission to retrieve said Codex.

Upon Completion, Ordis states that the Corpus have three pieces of the Arcane Codex, while the Grineer have two, and he muses about the Corpus believing the Codex to lead to a lost Orokin treasure.

After gathering all the Arcane Codices, Ordis realizes that the complete set of Arcane Codices form a code that can only be read by a machine, which he assumes is now unusable. Ordis' musings catch Maroo's attention, who informs him that the Arcane Codex she retrieved from the Orokin Derelict came from some kind of machine. With Ordis hypothesizing that said machine Lotus sends the Tenno on a mission to find the machine.

After fighting through waves on infested. The machine is located inside a large, special room with a pedestal in the middle, where the Arcane Codex can be uploaded. Instead of treasure like Maroo expects, the machine broadcasts an audio transmission with the following cryptic message:

"All-All is silent- Hushed-hushed and empty is-is-is the womb of the sky. All is silent and calm. Hushed and empty is the womb of the sky."

followed by a large unit of infested..

Ordis expresses his confusion at the Arcane Codex not being what they expected and expresses his apologies to Maroo. Despite her dismay, Maroo explains that she is used to low payouts due to being a freelancer, and with the threat of the Grineer gone, she sets off on her own way.