Stellar AI experiment

Make Stellaris AI smarter, more strategic, and more fun to play against!

Experimental Version

This is an experimental version of Stellar AI.

In this version, research job output is set to match Stellaris 4.3 vanilla values. The goal is to evaluate how this impacts AI performance, balance, and overall gameplay feel compared to the main version.

Based on feedback and observed results, I may either keep this as a separate version or incorporate parts of it into the main mod. As this is an experimental version, continued support is not guaranteed.

Focus is currently on stability, balance, and maintaining the core design.

Stellar AI shifts the AI toward a heavily research-focused playstyle. Research is treated as the AI’s main long-term goal, while industry, energy, rural production, expansion, and military development support that focus. The result is an AI that feels more coherent, competitive, and believable without relying on hidden AI-only bonuses.
The 4.4 update preserves this core design through a clearer progression: expand and research gradually from the capital, establish raw resources and consumer goods, reserve suitable research worlds early, then fill those worlds and accelerate science once the foundation is secure. Strong research and industry are later converted into fleet power.
The focus remains on stability, balance, and making a genuine research strategy viable.

• Standard empires use an early expansion-focused personality for roughly the first 40 years while at peace. War immediately restores their normal personality and military behavior.
• The AI invests deliberately in expansion, raw resources, and consumer goods instead of overcommitting to fleets or advanced production too early.
• Peacetime fleet spending is restrained while basic resources are unstable, helping build reserves for later wars.
• Early research remains meaningful on the capital. The first non-capital research role is reserved after the opening expansion, but laboratories wait until the economic foundation can support them.
• Aggressive and genocidal personalities still invest more heavily in military power and react earlier to threats.

Research remains the AI’s main long-term objective throughout the game.

• Stable empires begin a stronger research acceleration around year 45, after the main opening phase of expansion and preparation.
• Every settled AI empire reserves at least one non-capital research world. Additional good research candidates are admitted gradually and capped so science does not consume the economic base.
• Economic plans maintain stronger research targets through the midgame, endgame, and beyond-endgame stages.
• Basic resources, consumer goods, strategic resources, and industry are managed to sustain research rather than competing with it blindly.
• Technological growth is converted more reliably into advanced production, fleet strength, and late-game competitiveness.

The intended result is a natural snowball: a stable economy supports research, then research strengthens the economy and military.

Stellaris reduced the base output of standard researcher jobs from the older level of roughly 6 research to 3. Stellar AI raises the core Physicist, Biologist, Engineer, Calculator, and Brain Drone researcher families to 5, with matching adjustments to their direct research variants.
This shared balance adjustment is central to the mod’s design. It makes a heavy research strategy genuinely viable and allows sustained investment in laboratories to create a noticeably more advanced opponent. It applies equally to player and AI jobs; it is not a hidden AI bonus. Unique event and special-mechanic jobs keep their vanilla outputs.
Players who prefer the current vanilla researcher output can use the vanilla job levels mod page linked above.

• Shared crisis and readiness states coordinate economic plans, construction, research, and fleet spending instead of relying on overlapping threshold checks.
• Generator, Mining, and Farming zones and their supporting buildings are prioritized more strongly when the relevant resource is under pressure.
• Consumer goods are protected in the opening economy: Factory development is favored before additional mixed-industry or Foundry specialization during shortages.
• Machine empire economic plans put stronger emphasis on energy and minerals when their economy is under pressure.
• Aggressive peacetime fleet rebuilding requires a secure economy, while stable empires convert surpluses into military power more reliably.

Once war begins, the AI treats it as a survival situation. Peacetime shortage guards no longer throttle military spending: the empire remains committed to rebuilding and reinforcing its fleets.
Settled AI empires also use a simple monthly market stabilizer in peace and war: sell genuine surpluses first, then buy deficits and critically low resources with the proceeds. Trades use live prices, preserve protected reserves, allow at most two sales and two purchases per month, and never sell alloys.

Planet specialization is based more strongly on how a planet is actually developing, rather than only on theoretical district potential.

• Generator, Mining, and Farming worlds prioritize districts and zones already in use, relevant planetary modifiers, and current empire needs.
• Industrial planets transition more reliably into Factory, Forge, or Industrial worlds when real industrial commitment exists.
• Research planets receive stronger specialization support and avoid worlds already committed to incompatible roles.
• Urban and Unity designations are less likely to displace a clear rural, industrial, or research specialization.
• Stronghold construction and military designations are restrained to prevent excessive fortress development.

An event-driven commitment system follows how AI planets develop, discouraging unsuitable designations while allowing worlds to change roles naturally.

The mod has been rebuilt on the current Stellaris 4.4 definitions rather than simply carrying forward old files.

• Shared buildings, jobs, zones, colony types, personalities, economic plans, strategic resources, and AI budgets retain current 4.4 mechanics.
• Arkship construction, upgrades, resource costs, colonization restrictions, and Nomad spending categories remain available.
• Nomad-only buildings, jobs, zones, and designations remain controlled by vanilla Stellaris rather than receiving speculative balance changes.
• Settled-planet specialization penalties and emergency market systems do not interfere with Arkships or the Nomad economy.

For best results, use approximately 0.7x-1x habitable planets.

Start around Ensign; Captain is a reasonable upper limit for many players. Strong builds may prefer higher settings.

Place Stellar AI near the bottom of the load order unless another mod’s overlapping changes should take priority.

Supported Stellaris version: 4.4.*
A fresh 4.4 game is recommended. Continuation of 4.3 saves is not supported.
AI overhauls and mods replacing the same economic, colony, job, building, or zone definitions are incompatible. Other content mods depend on their overlap.

Please do not reupload or fork Stellar AI without prior permission. Compatibility patches, submods, and integrations are welcome with credit.