Stellaris Summer Experiments: Vigilance Espionage, Arc Furnace and Nomad Harvesting Rights

Stellaris Summer Experiments are not a roadmap. Dev Diary #429, published on 20 August 2026, says so itself: nothing shown is guaranteed to ship, and nothing has been reviewed, playtested or verified by QA. Paradox presents nine prototypes born over the summer, including a full rework of espionage.

Update, 26 October 2026: Stellaris 4.5 Cygnus was released on 22 September after nine beta updates. Harvesting Rights, which entered the beta on 27 August, were pulled from 4.5 on 17 September; Paradox expects them to return in a future release. The Vigilance system and the espionage assets do not appear in the beta notes we reread. Willpower, which announces ideological espionage updates, arrives on 23 November alongside Stellaris 4.6 Corona Borealis (details here).

An openly rough draft

The diary is introduced by Alfray Stryke, who recalls the tradition: every summer the team experiments with ideas that may or may not enter the game. Each section is then signed by the developer behind it. The 4.5 Cygnus open beta had started in the first week of July, and Update 6 was just arriving. It already carries one concrete change: Hedonist pop growth requires free housing and amenities, and stops while the empire runs a consumer goods deficit.

Espionage: Vigilance at the center

The rework comes from Cosmogone, a member of the team who says they have wanted to improve this system since being hired five years ago. The diagnosis is blunt: espionage has been considered underpowered since release, slow to set up, and its operations pay little for too many clicks. That weak payoff was deliberate: the team feared an empire being ganged up on by several spies at once.

The first piece is Vigilance, a value every empire has. It rises with each completed operation, then slowly decays back to its base. From 20 upwards it grants passive bonuses to encryption, to the cost and difficulty of hostile operations, and, at higher levels, to asset capacity.

Several empires targeting the same victim push Vigilance up faster than it falls. Above certain thresholds, Vigilance events trigger. Some help the defender. Most punish active networks: reduced infiltration, destroyed assets, envoys taken out, and the whole network destroyed at the highest level.

Assets, balance and quality of life

To offset that risk, existing operations are buffed. Sabotage Starbase now deals real damage, Smear Campaign lets you choose a target, and sacrificing assets adds bonus effects. The relative gap between encryption and codebreaking, capped at 4, rises to 6. Each point is worth 10 maximum infiltration, 20% infiltration speed and 1 less operation difficulty.

Ten new Upgrade assets, obtained through the Upgrade Network operation, give powerful passive effects but slowly raise the target’s Vigilance. The asset count starts capped at 6. Civics, traditions and the new Web Weavers perk raise it, and the target’s Vigilance lowers it. Past the cap, no operation can be run.

On the interface side, the diary lists sub-category icons for operations, spy networks in the outliner and a counter-intelligence readout in the top bar, which may still change.

Harvesting Rights and the Arc Furnace

The two economic prototypes are the only ones that reached the beta before release. Harvesting Rights, a frequent request since Nomads, are a trade deal: the nomadic empire harvests freely inside a settled empire’s borders, which receives an agreed percentage. In return, the settled empire can no longer issue harvesting contracts or negotiate these rights with another nomad. The nomad, however, can sign several.

The Arc Furnace, for its part, unlocks Smelting Processes at tier 3 instead of alloy production alone. In Update 7, switching mode costs energy and locks the furnace for 720 days. Paradox sees it as a way to open the door to more varied megastructures, and is also exploring a unified “Structure Capacity” for starbases, waystations and megastructures.

Nanites, mercenaries, flags and random empires

The rest of the diary is about comfort. Nanite swarms would count as a single ship even though each growth stage displays two. Mercenary enclaves would take on their patron’s colors, and the player would direct how they build their fleets. Randomization buttons, signed by pthooie, would roll ethics, civics or traits at random without wiping your own picks. An in-game flag editor and a new empire selection screen complete the list.

At the 4.5 release, border, fill and ship colors become adjustable independently of empire colors. macOS also goes native on Apple Silicon, a change whose early beta feedback, according to the diary, points to a massive performance gain.

What to watch

What matters is how much of this survives. On paper, Vigilance gives espionage a real cost of doing business, and the encryption gap raised to 6 rewards empires that invest in codebreaking. In practice, only Harvesting Rights and the Arc Furnace reached the beta, and the first were pulled on 17 September. The watch point is Willpower on 23 November: its notes will show whether Vigilance and the Upgrade assets join the announced “Ideological Diplomacy and Espionage Updates”.