Terra Invicta is not a game you win in 20 hours. A full campaign spans 15-25 years of in-game time and 40-80 hours of real-time play, making it one of the most demanding grand strategy experiences on Steam. The alien invasion unfolds across three theaters — Earth politics, space industrialization, and fleet combat — and success requires simultaneous progress in all three. This walkthrough covers a complete campaign from 2026 to 2050 with faction-specific advice for the Resistance (best for beginners) and Humanity First (best for aggressive players). Each decision point includes the reasoning behind the choice so you can adapt the strategy to your own playstyle and faction.

Campaign Timeline Overview

Early Game: Groundwork and National Control (2026-2028)

The first two years determine the rest of your campaign. Your primary goal is to control two strong nations — one for science and boost production, and one with nuclear weapons for military deterrence. The strongest opening move for both Resistance and Humanity First is to secure Kazakhstan (for its space program and boost income from Baikonur Cosmodrome) plus a nuclear power — either the United States (highest GDP and military, harder to control) or China (high population for Mission Control, strong industrial base).

Resistance Decision: Choose the United States as your primary nation. The Resistance gains bonuses to diplomacy with democratic nations, making US control easier to maintain. The US provides unmatched military power for early alien ground force engagement and has the highest research output of any single nation. Use your second nation (Kazakhstan) purely for boost generation — build space program investments until you hit 50+ monthly boost income.

Humanity First Decision: Choose China as your primary nation. Humanity First gains bonuses to authoritarian control and military operations. China's massive population translates into high Mission Control capacity once you build the appropriate infrastructure, and its industrial output supports rapid military buildup. Secure Kazakhstan as your secondary nation for boost. Be aggressive with Purge and Coup operations — Humanity First can afford to burn diplomatic capital with other factions.

Councilor Recruitment and Management

Your councilors are your most important assets. Recruit 4-5 councilors in the first 12 months, prioritizing these stat distributions:

Decision Point: Your 5th councilor slot is flexible. Pick a Commander if you plan early military engagement (Humanity First); pick a second Persuasion specialist if you want to control more nations (Resistance). A Commander with 15+ Command can assault alien facilities and lead ground combat operations, which becomes critical when alien ground forces land en masse around 2035. A second Persuasion specialist lets you hold 4-5 major nations simultaneously, which generates more research and Mission Control but leaves you vulnerable to alien ground assaults.

Space Program and Early Industrialization (2028-2033)

Once your Earth power base is stable, shift priority to space. Research Space Mining and Orbital Shipbuilding as early as possible — these technologies are the gateways to all space-based industry. Build your first space station in Low Earth Orbit (LEO) as a research hub, then send probe missions to the Moon and Mars to identify high-yield mining sites. The Lunar surface provides water and metals; Mars provides fissiles and noble metals for advanced ship components.

Decision Point: Rush to Mars or fortify the Moon first? Rush to Mars. The Moon offers closer mining but Mars has richer deposits and is the strategic gateway to the asteroid belt. A faction that controls Mars controls the midgame resource economy. Build one token Lunar base for water mining (needed for life support), then redirect all boost and Mission Control capacity toward Mars colonization. Claim 3-4 Mars sites before the alien factions secure them — each lost Mars site to the Servants or Protectorate is a permanent resource loss for your faction.

First Combat Fleet and Alien Engagement (2033-2039)

Alien warships begin appearing in Earth orbit around 2033. These initial scouts are fragile — a single Monitor-class ship with missile loadouts can destroy one — but engaging any alien ship triggers an escalation spiral. The aliens respond to each destroyed ship by sending larger fleets. Your goal is not to destroy every alien ship immediately, but to build a defense fleet capable of surviving the initial retaliation wave.

Decision Point: Engage early or wait until you have a fleet? Wait. Humanity First players may be tempted to engage the first alien scout with a token combat ship. Do not. A lone Monitor killing one scout triggers a response of 3-4 alien destroyers within 6 months, which will annihilate your ship and bomb your space stations. Build a fleet of at least 6 Battlecruisers with coilguns and layered point defense before your first engagement. The aliens respect strength — a fleet that destroys their scouts in one volley and survives the retaliation without losses discourages further attacks for 2-3 years. A fleet that limps away with casualties invites immediate follow-up strikes.

Earth Defense and Alien Ground War (2039-2042)

Alien ground forces begin landing on Earth in significant numbers around 2035-2040, targeting nations controlled by anti-alien factions. These ground assaults spawn alien armies that conquer territory unless countered by military councilor operations or national armies. This phase is the most dangerous for Humanity First — alien ground forces prioritize extremist factions and can overrun your controlled nations within 12-18 months if ignored.

Resistance Decision: Invest in layered defense — maintain high military spending in your controlled nations (3+ pips), build armies in border regions, and station a Commander councilor with Assault Alien Facility capability on Earth. The Resistance can afford a defensive posture because its victory condition (research the aliens' weakness) does not require aggressive space expansion.

Humanity First Decision: Go on the offensive against alien ground forces immediately. Every alien army group that lands is a threat to your power base. Use military councilor operations and national armies to destroy alien forces within 3 months of landing. If an alien army consolidates control over a region, the alien administration mechanic kicks in and the region becomes nearly impossible to reclaim without a full military campaign. Humanity First's victory condition (destroy the alien wormhole gate) requires total space superiority, so preserving your Earth industrial base is critical.

Counter-Offensive and Victory (2042-2050)

The alien mothership arrives around 2042, marking the transition to endgame. This vessel carries overwhelming firepower and serves as a mobile base for alien operations in the inner solar system. Destroying the mothership is mandatory for both Resistance and Humanity First victory paths. Bring every combat ship you have built to this fight — no ship is too valuable to risk when the alternative is losing Earth. Expect to lose 30-50% of your fleet in the engagement.

Resistance Victory: After destroying the mothership, research Wormhole Theory to understand the alien wormhole technology. This unlocks a final research project that reveals the aliens' strategic weakness. Complete this project to achieve victory. The Resistance path emphasizes science and diplomacy — you can win without destroying every alien base if you maintain enough research output to complete the final project before alien reinforcements arrive.

Humanity First Victory: After destroying the mothership, push to the outer solar system. Build forward bases on Jupiter's moons (Europa, Ganymede) and Saturn's moons (Titan, Enceladus) to extend your fleet range. Locate and destroy the alien wormhole gate in the Kuiper Belt, then eliminate every remaining alien base in the solar system. Humanity First achieves total victory through annihilation — no negotiation, no diplomacy, no research breakthrough. This path is longer and more resource-intensive but thematically satisfying for players who want to crush the alien threat completely.

Frequently Asked Questions