Stellaris Dev Diary #433 - 4.5 'Cygnus' Preliminary Release Notes
The 4.5 'Cygnus' update reworks the Pop Ethics and Faction system and introduces new Fleet Doctrine policies to control the ship auto-designer.
Key Changes
- 1Complete rework of Pop Ethics and Factions into a percentage-based system (Save-breaking change)
- 2New Fleet Doctrine and Weapon Preference policies for granular control over ship auto-designs
- 3Federation laws added to grant free, automatic Commercial Pacts and Research Agreements
- 4Consecrate World reworked into a deterministic scaling empire-wide bonus
- 5Starbase weapon modules are now type-specific and automatically upgrade with technology
- 6Nomadic empires gain access to Knights of the Toxic God and Cosmogenesis content
- 7Independent selection of map border, fill, and ship colors in Empire Creation
- 8Branch Office influence costs significantly reduced for distant systems
- 9Biomorphosis ascension path completion time reduced by 50%
- 10Massive bugfix pass addressing Precursor spawning and galaxy-wide ethics wipes
All Changes
⚙️Gameplay Systems(5)
- changePops: Reworked Pop groups to use percentages for Ethics and Factions rather than strict division (Breaking Change).
- buffPops: Increased the frequency of Pop ethics and faction shifts.
- changeCyberization: Updated Cyberization policies; Limited Cybernetic trait removed and replaced by policy-based efficiency penalties for Spiritualists.
- changeTrade Policy: Trade Policy now correctly converts trade value gained from Commercial Pacts and Branch Offices.
- buffBiomorphosis: Biomorphosis ascension path completion time reduced by approximately 50%.
🚀Ship Design(5)
- newAuto-designer: Added Fleet Doctrine policy with six tactical roles to determine automated ship designs.
- newAuto-designer: Added Weapon and Defense Preference policies to steer auto-complete designs and tech research.
- changeStarbases: Starbase, Orbital Ring, and Waystation weapon modules are now weapon-type-specific and auto-upgrade with tech.
- removeStarbases: Removed Autocannons, Disruptors, and short-ranged weapons from Starbases and Orbital Rings.
- changeBio-ships: Biological ships are now affected by food deficits instead of energy deficits.
🛸Nomads(4)
- newNomads: Unlocked Knights of the Toxic God origin for Nomadic empires.
- newNomads: Unlocked Cosmogenesis for Nomadic empires.
- newNomads: Added nomad-compatible version of Storm Chasers with functional Storm Attraction for arkships.
- buffArkships: Scientific Arkships now gain +5% Deep Scanning Success Chance per Tier.
🤝Federations(3)
- newFederations: Added laws to grant members free, automatic Commercial Pacts, Wayline Pacts, or Research Agreements.
- buffTrade League: Trade League federations now automatically provide free Commercial and Wayline Pacts between all members.
- buffFederation Code: The 'Federation Code' technology now reduces Diplomacy influence upkeep by 25%.
⚖️Balance(5)
- changeConsecrate World: Reworked Consecrate World to provide deterministic empire-wide bonuses to Unity, Amenities, and Ethics Attraction (+10%/20%/40%).
- buffCybernetic: Cybernetic species trait job efficiency increased from +5% to +10%.
- buffBranch Offices: Branch Office base cost reduced to 75 Influence (from 75 + 75 per jump) with a new distance penalty of 5 per jump.
- nerfKnights: Increased base Knights upkeep by 0.15 alloys and 0.15 consumer goods.
- changeStellar Cannon: Stellar Cannon moved to Tier 3 tech and now requires Wormhole Stabilization and UV Lasers.
🐛Bug Fixes(4)
- fixEvents: Fixed a major regression where Precursor dig sites and Fear of the Dark hostile empires failed to spawn.
- fixEthics: Resolved an issue where pop and country ethics were being permanently wiped across the galaxy.
- fixSynaptic Lathe: Fixed Synaptic Lathes failing to purge pops in certain scenarios.
- fixDeep Scan: Corrected Deep Scan chances for anomalies (7%) and archaeology sites (3%) which were previously too low.
🖥️UI/UX(2)
- newEmpire Creation: Added independent selectors for map border, fill colors, and ship colors in empire creation.
- buffDyson Swarm: Dyson Swarm 'best systems' list now shows up to 12 systems with varied resource types.
Summary
Pop & Ethics Overhaul
The core of the 'Cygnus' update is a fundamental rework of how Pops interact with Ethics and Factions. Pops are no longer strictly divided; instead, pop groups contain percentages of various ethics. This is a breaking change that will invalidate older save games. Ethics shifting and faction conversion now occur more frequently, and the UI has been updated with verbose tooltips to show attraction modifiers.
Ship Design & Auto-Designer
Players and AI now have significantly more control over automated ship designs through new policies. Fleet Doctrines allow players to set tactical roles (e.g., brawlers vs. carriers), while Weapon and Defense Preference policies steer both the auto-designer and technology research priorities. Starbases and Orbital Rings have also been overhauled with type-specific weapon modules that auto-upgrade based on researched tech.
Nomad & Federation Updates
Nomadic empires receive expanded compatibility, gaining access to the Knights of the Toxic God origin and Cosmogenesis. Federations can now enact laws to provide free, automatic Commercial Pacts and Research Agreements among members. Additionally, empire customization has been improved with independent selection for map borders, fill colors, and ship colors.
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