Military 13

Lore & Background

The Factorio military tech tree reads like a catalogue of escalating desperation. You start with a humble turret bolted to a factory wall, fending off the first waves of biters. Then a cannon. Then a gun for your character's hands. Each step answers a new threat: faster enemies, tougher enemies, enemies that come from the water. By the time you reach the submarine line, the biters are no longer a nuisance—they are a tidal force, and your factory is an island in a sea of chitin and hunger. The Submarine Torpedo is the logical endpoint of that escalation. Where the Rocket Launcher scatters a handful of small explosions, the Torpedo is a single, deliberate, heavy strike. It fires slowly, it travels in a straight line, and when it hits, the water itself seems to flinch. In the fiction of the game, it represents the player's final answer to the alien ecosystem: not a skirmish, not a patrol, but a statement of intent delivered in a sphere of concussive force. Fans often treat the moment of researching Military 13 as a small ceremony. After grinding through blue-science labs and watching the progress bar crawl, clicking that final research slot feels less like a gameplay milestone and more like the last page of a very long, very violent book.

In Their Own Story

The ocean around Sector 7 had been red for three days. Not the clean red of biters—something thicker, something that moved in coordinated waves, pressing against the submarine's hull with a sound like grinding teeth. Kael sat in the cramped cockpit, the torpedo's charge indicator blinking amber. One shot. That was all the magazine held, and the targeting reticle was already drifting as the sub lurched over a submerged ridge. He lined it up. Not at the cluster nearest the factory—too close, the splash would crack the foundation. He aimed at the gap between the two largest formations, where the water was deepest and the shockwave would propagate outward in a clean ring. His thumb hovered over the fire key. "That's it, then," he muttered, more to himself than to the empty comms channel. He pressed the key. The torpedo left the tube with a low, guttural thump that he felt in his molars. For two long seconds it simply traveled, a dark dart cutting through the murk. Then the water turned white, and every biter within a hundred meters simply stopped existing, replaced by an expanding sphere of displaced ocean that slammed against the submarine and rolled away like a slow, silent wave. Kael exhaled. The charge indicator read zero. He put the sub in reverse and began the long swim home.

Reader's Guide

Military 13 (Submarine Torpedo) is the final node in Factorio's strictly linear military research chain. To reach it, you must research every preceding military technology in order: Military 1 (Turret) through Military 12 (Submarine Rocket Launcher). There are no branching paths or optional skips within the chain—each tech requires the one immediately before it as a prerequisite. The technology unlocks the Submarine Torpedo, a weapon slot for your submarine. Compared to the Rocket Launcher it replaces in terms of tier, the Torpedo fires far more slowly but deals significantly higher damage in a wider splash radius, making it ideal for clearing dense biter swarms in open water. It is a single-shot, high-impact weapon rather than a rapid-fire option. In practical progression, most players research Military 13 in the late blue-science or early purple-science era, after their submarine fleet is already established and biter pressure in water-rich biomes has become a persistent threat. Because it sits at the very end of the chain, you will almost always have access to it before you finish the game's main tech tree. For blueprint sharing: the Submarine Torpedo itself is a weapon, not a placeable, so it does not appear in blueprint saves. However, the submarine and its loadout can be part of a broader factory blueprint if you are sharing a complete base layout. The tech tree interaction is straightforward—once researched, the torpedo is available to any submarine built thereafter, no additional crafting step required.

Did You Know?

• The military tech chain in Factorio is strictly linear: you cannot skip any of the thirteen technologies to reach Military 13.
• The Submarine Torpedo has a noticeably larger splash-damage radius than the Submarine Rocket Launcher, trading fire rate for area devastation.
• Because submarines must remain in water to function, the Torpedo is useless in land-locked factory layouts, making it a purely naval weapon.
• Military 13 is the last technology in the Military group, meaning no further military research exists beyond it in the base game.