Archives of Nethys

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Chapter 1: Building Starships

Source Starship Operations Manual pg. 6

Interstellar Travel

Source Starship Operations Manual pg. 8
Triune’s Signal revolutionized space travel, making Drift technology the preferred method for interstellar treks across the galaxy. However, other forms of interstellar travel existed prior to the Drift. Many of these are still in use today, alongside other recent innovations in stellar drives. While some of these remain in the experimental stage, they provide intriguing alternatives to Drift travel.

Drift engines enable starships to overcome the limitations of traveling faster than light by entering another plane of existence. Most other interstellar drives also operate by using planar jumps. However, planar travel outside the Drift involves extremely expensive magical technology, often in concert with divine assistance, and such magic is usually tightly controlled by the groups and organizations that use it. As a result, Drift technology is the most commonly available means of interstellar travel, and ships using other methods to travel between stars are relatively rare. More guidelines on incorporating these alternative modes of travel can be found below.

Non-Drift Travel in your Game

Drift engines are the most widely used technology in the galaxy for interstellar travel, and the Starfinder RPG assumes that all starships use the Drift for journeying between worlds. The interstellar drives presented in this section are generally restricted to certain faiths or organizations and are intended primarily for NPC use. As always, the GM has final say on whether PCs have access to these starship systems, but be aware that adding these options could challenge the baseline assumptions of your game. While these alternative interstellar drives aren’t more powerful than standard Drift engines, they might introduce complications for certain types of stories.

If you want to outfit a published starship with one of these new options (such as giving an Inheritorworks Cathedralship an archon drive), you can simply replace the Drift engine with the interstellar drive and update the ship’s Drift rating to match the rating of the new drive. The ship’s BP total and PCU rating will likely not be completely accurate, but the discrepancies should not have much of an impact on play, especially if the ship appears only in a single encounter. Alternatively, you can rebuild the ship from scratch using the new engine, but you will likely have to make other adjustments to the ship’s stat block to accommodate the interstellar drive’s BP cost and PCU requirements.

Alternate Interstellar Navigation

Source Starship Operations Manual pg. 8
Traveling through the Drift relies on Drift beacons for navigation, and these beacons effectively divide the galaxy into two zones: Near Space (regions close to Drift beacons) and the Vast (everywhere else). These distinctions are meaningless to starships without Drift technology; the density of Drift beacons in a given region of space has no bearing on travel times through planes other than the Drift. Likewise, Absalom Station’s Starstone has no effect on travel outside the Drift—it takes just as long for a ship without Drift tech to reach Absalom Station as it does to get to any other point in that system.

For most of the non-Drift interstellar engines presented here, travel times are the same whether a ship’s destination is in Near Space or the Vast, and the actual distance between the starting point and the destination doesn’t matter. With the exception of fold gates, traveling within a system takes about 1d6 days, and traveling anywhere in the galaxy takes about 5d6 days (the same as travel to the Vast via the Drift), though more powerful engines can reduce this time. When traveling to a world using a non-Drift interstellar drive, roll the travel time, then divide the result by the engine rating of your starship’s interstellar drive to determine how long it takes you to reach your destination. For example, a starship with a planar aperture drive (engine rating of 2) traveling to a planet elsewhere in the galaxy would roll 5d6 and divide the result by 2. If you rolled 15, then the trip would take 7-1/2 days (don’t round down travel rolls). As with Drift travel, days spent traveling through other planes are no different for a crew than days spent in normal space. A starship can stop while traveling through another plane, but such breaks don’t count toward your travel time.

Interstellar travel through planes other than the Drift has its perils, as the planes of the Great Beyond are often more dangerous than the Drift. The risk of random encounters when traveling through other planes is always higher than in the Drift.

As with Drift-capable starships, for a starship to activate its interstellar drive to either exit or enter the Material Plane, it must remain stationary with its conventional thrusters turned off for 1 minute.
  • Travel In-System (1d6 Days): Jumping between two points in the same solar system is moderately faster than moving between them in real space, but there is a 10% chance of random encounters on the plane being traversed.
  • Travel In-Galaxy (5d6 Days): Regardless of the target location or plane traversed, traveling to another location in the galaxy takes the same amount of time, and the risk of random encounters on that plane can be anywhere from 40% to 60%.
  • Travel Beyond the Rim: While technology capable of carrying a ship to another galaxy might exist, it is unknown to the galaxy at large; intergalactic travel using either Drift technology or non-Drift interstellar drives is currently impossible.

Interstellar Drives

Source Starship Operations Manual pg. 9
The interstellar drives below let you travel to distant star systems without using the Drift; their statistics appear here. For each ship, divide the base travel time by the drive’s engine rating; the better the rating, the faster you can reach your destination (See above). Interstellar drives have a PCU requirement and a maximum frame size. The cost in Build Points is based on the starship’s size category (for the purposes of this calculation, Tiny = 1, Small = 2, Medium = 3, and so on). Also, most of these interstellar drives have the restricted special property.

Restricted: This particular starship component is typically only available to a specific group or organization, listed in parentheses.

Starship Weapons

Source Starship Operations Manual pg. 12
A plasma torpedo or particle beam can get the job done, but clashes between the Pact Worlds, the Veskarium, the Swarm, and other factions have fueled unbridled innovation. Now, whether you delight in vaporizing enemy shields, tricking foes into entering your minefields, overriding other starships’ computers, or obliterating numerous targets with a single line of energy, you’ll find a plethora of devious new options on the following pages.

The new starship weapons in this chapter use the rules presented starting on page 303 of the Starfinder Core Rulebook. The weapons appear in tables on pages 18–19, grouped first by weapon class (light, heavy, capital, or spinal-mount weapons) and then by type (direct-fire, ECM, melee, or tracking). The new ECM and melee starship weapon types appear on this page, and new starship weapon special properties appear below. In addition, sidebars accompanying these new weapon types and properties detail new starship crew actions involved with these technologies.

Starship Weapon Types

Source Starship Operations Manual pg. 12
In addition to direct-fire and tracking weapons, this section introduces two new starship weapon types: ECM modules and melee weapons.

Electronic Countermeasure Modules

Source Starship Operations Manual pg. 12
Electronic countermeasure (ECM) modules are a type of powerful instrument designed to foil an enemy starship’s sensors, impair a starship’s systems, and in some cases alter the battlefield itself. ECM modules must be installed on weapon mounts, but they are activated by a science officer during the gunnery phase. ECM modules follow the same rules for range and quadrant targeting as conventional starship weapons.

When activating an ECM module, a science officer attempts a special gunnery check, adding their ranks in the Computers skill but adding neither their base attack bonus nor their ranks in the Piloting skill, and adding their Intelligence modifier in place of their Dexterity modifier; an NPC officer typically has a gunnery modifier equal to that of the gunner’s gunnery modifier. Compare the result of this gunnery check to the target’s Target Lock (TL). If the result equals or exceeds the target’s TL, the science officer hits and applies the ECM module’s effects. Due to the interference created by shields, starships with functioning shields in the targeted quadrant gain a +2 circumstance bonus to their TL against ECM modules. ECM modules do not deal critical damage.

Melee Weapons

Source Starship Operations Manual pg. 12
A melee weapon uses some part of the starship to induce a direct collision between the attacking and defending starships, targeting the opposing vessel’s AC. Melee starship weapons always have a range of 1 hex, even if a special property would otherwise change the weapon’s range.

Related Rules

Weapons (Source Starfinder Core Rulebook pg. 303)

Starship Weapon Class: Spinal-mount

Source Starship Operations Manual pg. 12
Any Supercolossal starship can mount multiple capital weapons, but the dreaded ultranought can support even larger ordinance, known as spinal-mount weapons. These immense devices of destruction are built along the vessel’s entire length and are integrated into its core, channeling the power of the ship’s engines and reactors into massive, direct-fire attacks that obliterate most targets. A Supercolossal starship can mount at most one spinal-mount weapon, and a spinal-mount weapon must be mounted in the front quadrant.

A spinal-mount weapon must charge before firing. The starship’s engineer can begin charging the weapon as an engineer action during the engineering phase if they succeed at an Engineering check (DC = 10 + 1-1/2 × the starship’s tier) to activate the weapon. The weapon charges for the duration of that round and continues charging during the subsequent round.

On the third round, during the gunnery phase, the spinal- mount weapon can be fired with the shoot gunner action. Because aiming a spinal-mount weapon requires moving the starship, the gunner gains a +2 bonus to their gunnery check when using their ranks in Piloting, instead of their base attack bonus, to calculate their gunnery bonus for the weapon. If the gunner wants to use their base attack bonus, they gain a +1 bonus to their gunnery check if they are trained in Piloting. Additionally, if the gunner fires no other weapons during the round when they fire the spinal-mount weapon, it deals an additional 1 damage per damage die. Once a spinal-mount weapon is fired, it cannot be activated or recharged again for 2d4 rounds.

If the gunner doesn’t fire a spinal-mount weapon on the first round that it is fully charged, a member of the crew must take an engineer or gunner action each round (requiring no skill check) to keep it on standby. If no member of the crew takes this action, the weapon’s energy dissipates as if it had been fired, and it cannot be activated again for 2d4 rounds.

Gunner Actions

Source Starship Operations Manual pg. 15
Gunners can use the following new actions to deploy drones and mines.

Deploy Drone (Gunnery Phase)

Source Starship Operations Manual pg. 15
You activate a starship weapon with the deployed special property, deploying a drone into a hex adjacent to your starship at the beginning of the next round.

Lay Mines (Helm Phase)

Source Starship Operations Manual pg. 15
You activate one of your ship’s weapons with the mine special property and place a number of mines up to the value listed with this special property. Each mine must occupy a different hex through which your starship traveled during its movement this round. Any of the listed number of mines not deployed with this action are wasted. You must use this action before the pilot begins moving the starship during the helm phase.

Science Officer Actions

Source Starship Operations Manual pg. 15
Science officers can use the following new actions to interact with ECM modules.

Activate ECM Module (Gunnery Phase)

Source Starship Operations Manual pg. 15
You can activate one of your starship’s ECM modules. If you use an ECM module mounted on a turret, you can target a ship in any arc.

Rapid Jam (Gunnery Phase, Push)

Source Starship Operations Manual pg. 15
You can activate any two of your starship’s ECM modules, regardless of their arc. Each check attempted with these modules this round takes a –4 penalty.

Recall Beacon (Helm Phase)

Source Starship Operations Manual pg. 15
You configure your starship’s coordinates to one of your starship’s active warp pucks. If you succeed at a Computers check (DC = 15 + 1-1/2 × your starship’s tier) before your starship’s movement for the round, your starship instantly moves to the warp puck’s hex while maintaining its facing. For every 5 by which you exceed the check, you can either increase your starship’s size modifier by 1 for the purpose of determining the maximum distance your starship can teleport to the puck, or you can turn your starship once. If you attempt to teleport your starship to a warp puck that is beyond the module’s maximum range, your starship does not move and the puck is destroyed.

Insidious Electronics (Gunnery Phase, Push)

Source Starship Operations Manual pg. 15
At 6th level, you can spend 1 Resolve Point to activate any one of your ECM modules that targets a starship. If you succeed, you gain the benefits of either the scan (one piece of information) or target system science officer action, in addition to the effects of the ECM module.

Pilot Action

Source Starship Operations Manual pg. 17
A starship’s pilot can perform the following stunt.

Ramming Speed (Stunt)

Source Starship Operations Manual pg. 17
The starship increases its distance between turns by 2 (to a maximum of 4) and moves up to its speed, but it can move through 1 hex occupied by an enemy starship that has already moved during this helm phase. To perform this stunt, you must first succeed at a Piloting check (DC = 15 + 1/1-2 × your starship’s tier). If you succeed, you then attempt a gunnery check against the enemy starship’s AC upon entering that starship’s hex.
If the gunnery check succeeds, your starship collides with the enemy starship, dealing collision damage to each based on your starship’s speed and the sizes of the two starships. The base collision damage equals 1d4 × half your starship’s speed, plus an additional 1d4 damage × a value based on your starship’s size (for the purpose of this calculation, Tiny = 1, Small = 2, Medium = 3, etc.). The enemy starship takes the full damage to the struck quadrant, and your starship takes half this damage to its forward quadrant, after which your movement ends. If your starship has a ramming weapon, add the ramming weapon’s damage to the damage to the enemy starship. If your starship is one size category smaller than the enemy ship or larger, you push the ship 1 hex in the direction your ship is facing. If this would push the ship into an occupied hex, the ship does not move but instead takes additional damage equal to your starship’s tier. If your starship is more than one size category smaller than the enemy starship, your starship returns to the hex from which it entered the enemy ship’s hex, facing that starship.
If the initial Piloting check fails, your starship still moves as described and doesn’t attempt the gunnery check, but the movement provokes a free attack from that starship as normal. If the Piloting check is successful yet the gunnery check fails, your starship still moves as described, but the movement doesn’t provoke a free attack from that starship.

Upgrading Weapons

Source Starship Operations Manual pg. 17
Starship weaponry can accommodate considerable modification, whether from corporate innovators or independent mechanics. A starship’s crew can incorporate one or more of the following upgrades to a weapon by multiplying the weapon’s BP cost by the listed value. Any restrictions on the types of weapons to which an upgrade can be applied are listed in the upgrade’s entry.

Table 1-2: Weapon Upgrade Costs


Alternate Armors

Source Starship Operations Manual pg. 20
While shields are the most common means of averting harm, starship engineers have experimented with a broad array of supplemental defenses to ensure occupants’ safety—anything from layering armor upon armor to projecting energy barriers that deflect rather than absorb impacts. With the proliferation of Drift travel, these various technologies have become more commonplace across different shipyards and manufactories.

Ablative Armor

Source Starship Operations Manual pg. 20
By layering inexpensive metal and composite plates over existing bulkheads, a ship can absorb initial damage to its hull before its essential components become vulnerable to attack or hostile environments. However, thicker plates are bulky and interfere with the maneuverability and handling of starships. Ablative armor grants a starship temporary Hull Points to each quadrant, usually distributed evenly. When a starship would take damage to its Hull Points, it first reduces its temporary Hull Points from ablative armor in that quadrant. Once a starship’s temporary Hull Points in a quadrant are reduced to 0, any further damage to that quadrant not absorbed by shields is applied to the ship’s Hull Points. The loss of temporary Hull Points does not count toward the starship’s critical threshold, though for all other effects, any attack that reduces a starship’s temporary Hull Points is treated as though it had dealt Hull Point damage to the target.

In most cases, ablative armor is applied evenly, distributing its temporary Hull Points between all four quadrants. However, a starship can support uneven distribution at the cost of the starship’s handling, though the vessel can add only a limited amount of extra armor to smaller hulls. If a starship’s ablative armor is not installed evenly across all four quadrants, reduce the starship’s base frame Piloting modifier by 1 (minimum –3). Reduce the Piloting modifier by 1 if the temporary Hull Points granted by ablative armor exceed the starship’s Hull Point total. A starship cannot support ablative armor if its temporary Hull Points exceed twice its standard Hull Point total.

Ablative armor can be restored only when the starship undergoes repairs, and it is repaired at the same rate and cost as standard Hull Points. A starship’s Hull Points must be fully repaired before making repairs to any temporary Hull Points provided by ablative armor.

Related Rules

Armor (Source Starfinder Core Rulebook pg. 297)

Deflector Shields

Source Starship Operations Manual pg. 20
Whereas conventional starship shields absorb attacks entirely until they are depleted, some engineers insist that shields are most effective when deflecting attacks, blunting their force or causing them to miss entirely. Deflector shield technology reduces damage from incoming attacks and increases a starship’s AC and TL, though each successive attack depletes the shields’ defensive potential. Deflector shields and conventional shields create fields that interfere with each other, so only one of these two defenses can be installed on a starship.

Fully functioning deflector shields provide a starship the defense value (DV) listed in Table 1–5 to each quadrant. Whenever the starship would take damage, it ignores an amount of that damage equal to its defense value in that quadrant. Deflector shields are twice as effective against attacks from melee, ramming, and ripper starship weapons, so the starship ignores double the amount of damage from such attacks. Any attack that would ignore a fraction or all of a target’s shields instead reduces the amount of damage the deflector shields ignore by an equal amount, rounded in the defender’s favor (e.g., deflector shields with a defense value of 5 would reduce damage from a burrowing weapon [Pact Worlds 153] by 3). While the deflector shields’ defense value in a quadrant is 1 or higher, the shields increase the starship’s AC and TL against attacks in that quadrant by the listed amount.

Whenever an attack or effect damages a starship’s Hull Points, the deflector shields’ defense value in that quadrant also decreases by 1, reducing the amount of damage they can ignore. Weapons with the array or line special property that damage a starship’s Hull Points overwhelm its deflector shields, reducing their defense value in that quadrant by 2, whereas vortex weapons that deal Hull Point damage reduce the target’s deflector shields’ defense value in each quadrant by 1d4. Any successful attack by a weapon with the buster special property (or another special property that deals reduced damage to Hull Points) reduces the deflector shields’ defense value in the struck quadrant by 2, whether or not the attack damaged the target’s Hull Points. When a gunnery check results in a natural 20, any decrease to the target’s deflector shield’s defense value from the attack is 1 greater.

When an engineer uses the divert action to send power to shields, they increase the defense value of a single quadrant by 2, or the defense value of each quadrant by 1, up to the deflector shields’ maximum defense value per quadrant. For every 150 PCU provided by a starship’s power core, increase the defense value restored to one quadrant by 1. When a science officer uses the balance action, they can adjust their deflector shields’ defense values in the same way as they would shift or distribute Shield Points, though each quadrant must have a defense value of at least 1 afterward. When a starship is not engaged in combat or otherwise taking damage, the defense value for each quadrant regenerates at a rate of 1 per minute.

Related Rules

Shields (Source Starfinder Core Rulebook pg. 302)

Fortified Hull

Source Starship Operations Manual pg. 21
By reinforcing critical starship systems with extra-thick armor, a starship’s designer can limit catastrophic failures caused by incoming attacks. A starship can incorporate one fortified hull upgrade, which increases the vessel’s Critical Threshold (CT) value by an amount based on the fortified hull’s material and the starship’s size category (for the purpose of this calculation, Tiny = 1, Small = 2, Medium = 3, Large = 4, etc.). A fortified hull is a passive system that requires no PCU to function.

Reinforced Bulkheads

Source Starship Operations Manual pg. 21
By dramatically strengthening a starship’s bulkheads and other interior walls, its designer can reduce the odds of catastrophic system damage when the starship sustains damage. Whenever the starship would sustain critical damage, there is a percent chance based on the reinforced bulkhead’s fortification rating that the critical damage effect is negated (though the attack still deals damage to the starship). The cost of reinforced bulkheads is based on the starship’s size category (for the purpose of this calculation, Tiny = 1, Small = 2, Medium = 3, Large = 4, etc.).

Supercolossal Starships

Source Starship Operations Manual pg. 36
Although immense dreadnoughts represent the pinnacle of starship engineering in most starfarers’ minds, the rare Supercolossal spacecraft dwarf even those infamous ships. These titanic starships are of such extraordinary proportions that only the mightiest navies can afford to field one, and their hulls might represent the mineral wealth of entire moons. This section presents the new Supercolossal size category of starship and rules for creating and operating these leviathans.

Supercolossal starships have two typical forms: base ships and ultranoughts. Base ships are effectively floating cities, ideal for colonization or long-range exploration—some are even independent political entities in their own right. Ultranoughts are the most powerful vessels their respective militaries can field, designed to carry unprecedented firepower, armor, and durability while supported by cruisers, escorts, scouts, supply tenders, and other ships. Supercolossal vessels are over 6 miles long and take a –8 penalty to AC and TL. Except as detailed here, these starships use the normal rules presented in Chapter 9 of the Starfinder Core Rulebook.

Base Frame

Source Starship Operations Manual pg. 36
Each base frame determines a starship’s size, maneuverability, hull strength, starting weapon mounts, number of expansion bays, and other capacities.

Base Ship

Size Supercolossal Maneuverability clumsy (–2 Piloting, turn 4)
HP 450 (increment 75); DT 15; CT 90
Mounts forward arc (4 heavy), port arc (4 heavy), starboard arc (4 heavy), turret (2 capital)
Expansion Bays unlimited
Minimum Crew 150; Maximum Crew 100,000
Cost 250


Size Supercolossal Maneuverability clumsy (–2 Piloting, turn 4)
HP 550 (increment 100); DT 20; CT 110
Mounts forward arc (2 capital, 2 heavy, 1 spinal mount), port arc (2 capital, 3 heavy), starboard arc (2 capital, 3 heavy), turret (1 capital, 2 heavy)
Expansion Bays unlimited
Minimum Crew 250; Maximum Crew 5,000
Cost 350


Source Starship Operations Manual pg. 36
Supercolossal ships follow special rules for starship systems.

Power Core: Supercolossal ships require massive power. A Supercolossal ship can mount one of the Supercolossal power cores shown in the following table. If a Supercolossal starship has a Supercolossal power core, the vessel can also have up to four backup cores; those cores must be designed for Huge or Gargantuan starships. If a Supercolossal starship doesn’t have a Supercolossal power core, the vessel can instead mount up to five power cores designed for Colossal ships.

Titan LightSc70050
Titan HeavySc95060
Titan UltraSc1,20070

Thrusters: Supercolossal ships depend on enormous thrusters that focus on speed, since the maneuverability of ships of this size is hard to improve.

Sc4 thrustersSc4+130016
Sc6 thrustersSc6+040020
Sc8 thrustersSc8–150024

Armor: A Supercolossal ship has a size multiplier of 8 for determining its armor’s Build Point cost.

Computers: A Supercolossal starship’s main computers and integrated control module (ICM) function in the same way as other starships’ computers do, with three exceptions. First, such an immense starship requires a mk 4 computer or better. Second, a Supercolossal starship can support a second computer system so long as the second system has a lower mark value than the primary system (e.g., a mk 4 trinode computer with a secondary mk 2 mononode computer, granting bonuses of +4/+4/+4/+2).

Third, a Supercolossal starship can augment its primary computer with network nodes—subordinate systems that increase the number of officers who can benefit from the ICM each round by one—so a mk 6 duonode computer with two mk 6 network nodes can grant a +6 circumstance bonus four times each round. A network node functions only if connected to a computer of an equal mark value. Network nodes could represent any number of means of supplementing a computer’s processing power and accessibility, such as a dedicated technological system, a hardwired cybernetic undead creature, a biotech calculating organism, a magitech information crystal, or any of myriad other devices.

Mk 4 network node+4284
Mk 5 network node+52105
Mk 6 network node+63116
Mk 7 network node+73137
Mk 8 network node+84158
Mk 9 network node+94179
Mk 10 network node+1051910

Crew Quarters: On a Supercolossal ship with common crew quarters, the vessel’s size enables 10% of the crew to have good quarters and 1% to have luxurious quarters at no additional cost. On a Supercolossal ship with good quarters for the majority of the crew, 10% have luxurious quarters at no additional cost.

Drift Engine: A Supercolossal starship can mount only a Signal Basic Drift engine, at a cost of 16 BP.

Expansion Bays: A Supercolossal ship uses the same expansion bays as other starships do, but can hold an unlimited number of expansion bays. Any expansion bay in a Supercolossal ship represents numerous chambers grouped together over a wide area, augmented with reserve systems and retaskable configurations. For example, an arcane laboratory on a Supercolossal ship indicates not a single lab, but the facilities that allow the entire crew to perform tasks requiring an arcane lab. That said, some expansion bays work differently for Supercolossal ships.

Cargo Holds: Supercolossal ship frames have one cargo hold for every 10 BP of the frame’s cost. Additional holds cost 5 BP each.

Hangar Bay: A Supercolossal ship’s hangar bay can accommodate up to eight Medium ships, with two Small ships or four Tiny ships taking the same space as one Medium ship. Expanding an existing hangar bay to accommodate eight more Medium ships increases the hangar bay’s cost by only 1 BP.

Exclusive Expansion Bays: A few expansion bays are available only to Supercolossal ships.

Drift booster4020
Recycling system21

Drift Booster: A Drift booster is a rail for launching smaller ships into the Drift from within a Supercolossal vessel’s hangar bay. A smaller ship that launches from within the Supercolossal vessel’s hangar bay using the Drift booster can temporarily raise its Drift engine rating by 1. This increase lasts only as long as the smaller ship stays in the Drift and on the same course after launching using the Drift booster. If the boosted ship changes course or leaves the Drift, this temporary increase ends.

Recycling System: A recycling system enables a Supercolossal starship to be nearly self-sustaining, operating independently for decades or even centuries. A combination of smelters, biomass processors, manufacturing, and UPB converters enables the ship to convert almost all its waste into goods and materials.