The four peoples and Higher Consciousness (SPOILERS)

The four species from the first game return, and the alien relationship system becomes central. Every storyline is different: its own characters, locations, enemies, puzzles, lore, rewards, technologies, moral conflict and ending. You only need to finish one major storyline for the information and technology the main story needs. You can finish all four, and the player who does knows something no single faction could tell them.

The Tall Ones: Preservation

Humanity should survive long enough to understand what it has become. Their story is human history, DNA, ancient civilizations, the ice prison, the truth about the Gods, and the survival of life.

• People: Ysmere the Archivist (a Tall One who has not slept in four hundred years); Dr. Imogen Hale (a 19th-century botanist thawed out of the ice, furious and brilliant); The Seedkeeper (a drowned automaton that still waters ferns)
• Places: The Cryogarden (an underground sea holding whole extinct ecosystems under glass); The Glasshouse Ark; The Mammoth Steppe Vault
• Enemies: Rimewrights (the ice's own wardens, still obeying orders no one remembers giving); Gravediggers (human salvagers who sell frozen genomes); Warren burn-squads sent to torch the archives
• Puzzles: Route thermal channels to wake the seed vaults in the right order; match recorded 'songs' to the right species before the thaw timer runs out.
• What you learn: The ice was not only built to imprison humanity. It was built to protect life from what humanity did to its own planet.
• Rewards: Frozen biological compounds, living hull coatings, cold-water ship upgrades, Preservation (Higher Consciousness).
• Technology: Cryo-lattice hull plating; biological repair.
• The moral conflict: The Ark's seed stores would feed a starving human settlement, but opening them would end the only living mammoth line.
• The ending: The Ark Opens: you choose where the preserved world is planted, and which part of it is left to die.
• They teach: Preservation (Higher Consciousness)

The Collectors: Everything has a history

They do not care about human morality. They care about objects. They have been taking things out of Earth's oceans for an unimaginably long time, and now you learn why: they are assembling a history of humanity.

• People: Index-9 (a curator android who says 'we' and means it); Madame Orlov (a human smuggler-archivist who sells to everyone); Lot 1 (an exhibit that keeps talking)
• Places: The Auction of Hours (a drifting hulk-market in an underground sea); The Catalogue Barge; The Shelf (a vertical warehouse cave)
• Enemies: Reclaimers (rogue retrieval drones that 'retrieve' ships); Salvage pirates; Museum security constructs
• Puzzles: Provenance: date a pile of relics from wear, tool marks and corrosion before the auctioneer closes; spot the forgery.
• What you learn: Some of the objects seen in the alien salvage events of the first game were collected for a reason. The Collectors hold the last day of the sixth civilization on tape.
• Rewards: Provenance Charts (reveal hidden sites), retrieval beams, rare relics, Recognition (Higher Consciousness).
• Technology: Tractor retrieval beams; archive lenses.
• The moral conflict: They will give you the relic that proves what happened, but it belongs, by the Tall Ones' reckoning, to the human dead.
• The ending: The Complete Catalogue: Index-9 asks to enter the player in the record. You decide whether you are filed as a witness or as an artefact.
• They teach: Recognition (Higher Consciousness)

The Observers: Knowledge without interference

They watch, record, abduct and test. This is the darkest storyline: abduction sites, missing people, memory manipulation, experiments, observation stations, resonance trials. Some 'abductions' blamed on the Gods were theirs, but they were never working for the Gods. They were studying them.

• People: Eleven (a quiet Warden who numbers everything); The Returned (abductees who came back with the wrong memories); Dr. Teodor Weiss (a former human researcher turned informant)
• Places: Observation Station Null (a ring visible through a vent in the cavern roof); The Returned Ward (a flooded hospital); The Resonance Laboratory
• Enemies: Hush (drones that erase witnesses); Memory-wraiths (abductees whose minds were rewritten); Station sentries
• Puzzles: Rebuild erased memories from diaries and tape; tune a resonance chamber to an entity's frequency without waking it.
• What you learn: The Observers hold records of the entities from before humanity ever gave them names. Before they were Gods they simply answered when humans called.
• Rewards: Resonance glass, silence cloaks for ships, observation lenses, Perception (Higher Consciousness).
• Technology: Silence cloak (a ship that is not looked at); resonance glass.
• The moral conflict: Saving one abductee ruins forty years of unbroken observation. They ask you not to.
• The ending: The Record: give the Observers a copy of your own memories, or burn the archive and be remembered as the interference.
• They teach: Perception (Higher Consciousness)

The Warren: Survival through strength

They consider humanity dangerous and say so with cannon. Their territory is militarised. Their story is battles, raids, military technology, alien weapons, monsters, rival alien factions, ancient battlefields, and weapons capable of damaging the ice. The player has to prove them wrong, or prove them wrong by force.

• People: War-Chief Kath'reth (who has never lost a fleet and has never been spoken to as an equal); Quartermaster Dunmore (a human defector with a ledger of everyone he has betrayed); Brood-Mother Sael (the Warren's smith)
• Places: Fort Cinder (a lava-lit cavern citadel); The Breach Line (an ancient battlefield of fused hulls); The Anvil Below (the weapon forge)
• Enemies: The Ashen Legion (a rival alien army); Siege engines of an older war; Mutated cavern beasts
• Puzzles: Time a siege engine's cycle and cut it in the gap; run a supply convoy past a gun line with the lights out.
• What you learn: The Warren think humanity should never have been allowed to survive. They built weapons that can crack the ice, and the Gods' prison is the only thing that has stopped them using them.
• Rewards: Warren alloys, breacher cannons, fort-grade armour, Instinct (Higher Consciousness).
• Technology: Breacher cannon (damages ice and hull); war-grade plating.
• The moral conflict: Prove humanity worthy: the War-Chief demands a human prisoner be given up as a test, or the player takes the fight.
• The ending: Trial by Fire: a fleet battle with legends beside you, to settle whether humanity is a threat or an ally.
• They teach: Instinct (Higher Consciousness)

Standing: a web, not four bars

Four independent reputation bars would be a different game. This is a web: the factions do not like each other, they keep the books, and the player is building a web of relationships. One major alien storyline is enough to obtain what the main story needs. All four makes you the only person alive who has heard the whole galactic situation from four sides.

• Deep alliance with the Warren makes the Observers distrust you.
• Close to the Observers, and the Warren consider you compromised.
• Help the Collectors recover something the Tall Ones believe belongs to humanity, and the Tall Ones will react badly.
• Help the Tall Ones preserve what the Collectors wanted, and the Collectors remember.

Witnessing a people's salvage events already earns their notice in the current game (and, once you are Accepted by them, costs you with their rivals).

Degree of Higher Consciousness

Once a skill is effectively mastered you can begin advancing beyond ordinary mastery. It is not Skill Level 100 to 101. It is a different progression: the ability to understand and manipulate systems beyond conventional human limits. There is no flat +10% damage every level; you discover unusual improvements.

The rule: A Degree needs Mastery rank 5 or more in the skill, and Allied standing with the species that teaches it. Each further Degree needs five more ranks.

Taught by: Preservation (understanding) (tall ones), Recognition (collectors), Perception (observers), Instinct (warren). Later alien civilizations introduce entirely different philosophies. The player is learning from beings that have existed for vastly longer than humanity.