The Second Dream

Stalker walks up to a platform, surrounded by floating Sentient fighters on all sides. As he walks up to the center of the platform, a disembodied voice speaks to him about the Stalker's vengeance and the Tenno's seeming immortality. As the Stalker drops the severed head of a Loki unto the platform, the voice reveals that the Tenno "essence" has been hidden from them by the Lotus, and tells him that he knows that it is found in a "womb in the sky". Using its powers, the voice gives Stalker new armor and a large greatsword with which to accomplish its mission. The Stalker asks for the voice's identity, to which it replies as Hunhow, Sentient destroyer of worlds.

The Lotus contacts the Tenno to warn them about the threat of the Sentient Hunhow, who has been infiltrating her mind. She also warns them about Hunhow using the Stalker to hunt down the Reservoir, the Tenno's weakness that the Lotus has kept hidden. The Tenno are sent to Uranus to infiltrate data from the Grineer on their knowledge of Hunhow, who they released after excavating him.

The first Data Vault hacked reveals that the Grineer had been excavating pieces of Hunhow, and that he is capable of controlling each part of him with his mind, making Lotus wonder if said mechanism is how the Sentient has been invading her mind. Infiltrating the second vault reveals it to have already been accessed and corrupted, thus Lotus entreats the Tenno to find another vault to acquire more data. Hunhow contacts Lotus at this point, telling her of his intent to restore the Lotus. While Lotus defiantly claims that he'll never find the Tenno, Hunhow tells her that he already knows due to his infiltration of her mind.

The final vault gives Lotus the final piece of data she needs, revealing it to be a personal message to her. Lotus excuses herself, telling the Tenno that she needs to contact the person who sent the message, before telling them to head to extraction.

The Lotus, fearing that Hunhow can listen in on her, tells the Tenno that the message she received was an offer for help. However Lotus does not reveal who said person is, only that she doesn't trust them. She then sends the Tenno to Cressida, Uranus to find a fragment of a Sentient.

Once the Tenno arrives at the mission site, the mysterious helper is revealed to be none other than Alad V, who claims knowledge of what they are looking for. Despite their antagonistic past, he asks the Tenno to trust him due to the greater threat of the Sentients.

Upon diving underwater and reaching the site of an Orokin shipwreck, Alad V, unwilling to completely guide the Tenno in finding the fragment, urges them to search the excavation site for it themselves, providing hints only if the players are near the objective. The actual objective at this point is to find a tunnel closed off by rocks, which can be destroyed to reveal a passageway leading out of the excavation site and into a large underwater cavern with a Sentient wreck. The fragment is found upon exiting the waters above the cavern, a Sentient relic that the Lotus says she could use to view the memories of her father. Once the Tenno interacts with the relic, Lotus sees a vision of the Stalker who is apparently confused, before realizing that she has been caught in a trap: interacting with the relic has allowed Hunhow to ascertain the location of the Reservoir, with the Stalker now en route to it. Alad V then tells the Tenno to hurry back to extraction

Back on the player's landing craft, Alad V asks the Lotus what "the Reservoir" is and whether it's a Tenno weakness. Lotus only tells him that he has already earned his favor from them, only for Alad V to counter that the Tenno are his investment, thus he wishes to see this through.The next mission takes the Tenno to a Corpus Outpost on Neso, Neptune. The fragment apparently lead Hunhow to a path leading to the Reservoir which passes through said outpost, and that in order to reach it Hunhow needs the Stalker.

Reaching the objective marker reveals an Orokin portal room, what Alad V calls a "Void Gate". On entering the room, the Stalker vanishes as the void portal collapses. A Sentient Conculyst or Battalyst will suddenly appear, a powerful enemy unit which the Tenno must defeat. Doing so will reveal the location of a Void Key the Stalker used in the portal room to Lotus' surprise. The Void Key must be inserted into the Torsion Beam Device at the center of the portal room to reopen the void portal, at which point the Lotus urges the Tenno to enter, stating that the Sentients will be unable to follow the Tenno there due to the Void being poison to them.

Upon arriving at the other side of the portal, Alad V tells the Tenno to find a nav console to figure out where they are. The nav console is located in a room with a window looking out at a sight that shocks Alad V: The Moon. Alad V explains that the Moon was thought to have been destroyed, expressing wonder at it being in the Void all this time and at the Lotus' ability to have put it there. The Lotus tells the Tenno that the Reservoir is the source of their power, and must be protected. Once the nav console is activated, the Lotus detects the Stalker leaving on a ship headed to the moon and urges the Tenno to find a way to follow him.

Alad V realizes that the Orokin Tower the Tenno are currently in is used to hide the Moon's location in the Void, thus suggesting that the tower should be disabled to allow Ordis to pick them up. To disable the tower, the Tenno must find a marked console hidden inside a retractable cover within a generator room and hack it, which will allow 4 more retractable panels in the generator room itself to become visible. These 4 panels will reveal a blue vial each that must be destroyed, but are protected by electric arcs. Once all 4 panels have been revealed and their vials destroyed, Ordis will contact the player to tell them to prepare for pickup.

Ordis mentions that he recalls having been to the Moon once, and that he is concerned for the Tenno. The Lotus explains that the Reservoir is the source of the Tenno's power, and that its secret drove the Stalker mad. The Lotus asks the Tenno for forgiveness, telling them that they must now protect the Moon by keeping it within the Void.

Arriving on the Moon, the Tenno are tasked with stopping Stalker from reaching the Moon's Void Control Room, whose aim is to initiate a void collapse that will destroy the Moon, which will destroy the Reservoir and in turn the Tenno along with it.

Before players can reach the Void Control Room however, the Stalker initiates the collapse, which causes shadowversions of hostile Infested to appear throughout the complex. The Lotus decides to pull the Moon out of the Void and back into normal space to prevent its destruction, tasking the Tenno to reorient the Moon by reactivating the Void Control Room's void compasses.

Upon reaching the Void Control Room, players must first hack a console at the center of the room, and then reactivate three void compasses located in three towers. Hacking the central console will make the Shadow Stalker appear, the improved version of Stalker with new weapons and abilities. Just like a normal assassination by Stalker, if the Tenno is able to lower the Stalker's health far enough, he'll disappear, though this will be much harder than before due to Shadow Stalker featuring similar resilience as the Sentients. When the compasses are reactivated, Hunhow threatens Alad V for being Orokin, causing Alad V to bid farewell to the Tenno as he has apparently been found by Hunhow, while reminding Lotus of their deal.

With all compasses reactivated, Lotus tells the Tenno to get to the Pendula, which are devices that maintain the Moon's stability in the Void, and deactivate them. There are four such Pendula located in four pillars in the center of the room they are located in, protected by a floating and teleporting Security Eye that will shoot waves of slow-moving destructive energy at players. As both the Pendula and the Security Eye are immune to any form of attacks, in order to destroy the Pendula the Tenno must trick the Security Eye into attacking the pillars by making the Security Eye shoot into the Pendula's direction. Care must be taken after the first Pendula is destroyed, as the Security Eye will begin to perform wide scale area-of-effect attacks after its standard beam attack

After all the Pendula are destroyed, the Lotus orders the Tenno to get to extraction as soon as possible. Along the way, disembodied voices belonging to a man named Ballas and a woman named Margulis conversing to each other can be heard, arguing about the fate of "devils".

The Lotus informs the Tenno that they will have to act fast, as the Moon is now exposed and the Stalker is already en route to destroy the Reservoir. Once again, the Tenno arrives on the Moon. As the Tenno proceeds through the level, more disembodied voices similar to the previous mission will be heard, revealing more of Margulis and her work, along with the Orokin's reactions to it.

At the end of the level is the Reservoir, a place with water falling into a small pond below.the tenno is walking towards the Reservoir as it observes a golden flower-shaped pod emerging from the waters. The pod opens up, revealing a person wearing a black bodysuit, which the pod then carries out on a chair. The person is dumped in front of the Tenno, resulting in the screen flickering and breaking up, with the Warframe suddenly falling limp, before the view blacks out. The disembodied voice of Margulis was heard: At this message, the person in the bodysuit crawls over to the Warframe, and then touches it. The act reactivates the Warframe, and makes it carry the person in its arms. The Stalker appears afterwards seemingly ready to kill them, but hesitates, earning the ire of Hunhow who proclaims that Stalker's hate is weak, before sending the Stalker away to allow Sentient fighters to finish the job

At this point, the player must now carry the person to the extraction point while being followed by Sentient battle drones. The Warframe's mobility is greatly reduced while carrying them, walking much slower and being unable to use any parkour moves, including sprinting or jumping.

Back aboard the player's ship, the Warframe still carries the person in its arms, and the Lotus tells them to head deep inside the Orbiter section to find the Somatic Link, located inside a room at the very bottom rear of the Orbiter. Unbeknownst to them, the Stalker has infiltrated the spacecraft and is ordered by Hunhow to kill the Tenno before they reach the Somatic Link, which is the device at the very rear of the room. The Stalker will then proceed to attack the Tenno, firing red energy waves that can push back the players a significant distance away. The player must dodge the Stalker's attacks and/or block them with their energy beam attack to reach the Link. Once the player reaches the Link, they must use the energy beam to feed energy into the Link via a blue energy sphere at the top of the Link. When the Link has received enough energy, an energy blast from the Somatic Link will push the Tenno back, forcing the Tenno to repeat the process of going past the Stalker and refilling the Somatic Link. This must be done three times.

Once the Somatic Link has been filled three times, the person and the Warframe are both blown back from the energy dispersion, separating them. The Stalker stands before the Warframe, lifeless again after being separated from the Operator's touch. The person cowers in fear, as Hunhow monologues how the Warframe (up to this point thought to be the Tenno) is a "metal puppet" to the real Tenno, who is actually the helpless person from the Reservoir. After stabbing the Warframe with his greatsword War, the Stalker approaches the Tenno and proceeds to choke them. Inexplicably, the Warframe revitalizes and breaks War in half, dispelling Hunhow's control, causing the Stalker to be overcome with immense pain. The Stalker flees, releasing a blinding flash that knocks the real Tenno unconscious.

The Lotus then appears, personally carrying the Operator into the Somatic Link. The Lotus reveals the Operator is the Tenno themselves, their true form. The Lotus begins asking questions to see how much the Tenno remembers, and helps them recover some of their memories. She explains how one of the Orokin, Margulis, helped save them from their uncontrollable powers by creating a dream-state for them to live in. The Lotus further explains that Margulis was killed by the Orokin Executors and her ideas were used by them to create "Transference", which allows the Tenno to control their powers through a remote "surrogate", the Warframe.