Stars Without Number
Advanced Starship Combat
Advanced Starship Combat
The following rules are meant to make starship combat somewhat more survivable, but still have serious consequences (And still be potentially lethal if a critical system blows, even though it buys you some more time. This isn’t necessarily a good thing.)
The AC of the ship is calculated normally – base AC minus the pilot’s skill. It is much harder to improve the AC of a slow ship than to improve a character’s natural AC. AC represents the difficulty of hitting the ship.
Armor is also calculated normally – subtracted from the incoming damage of each individual hit.
Ships do not have HP in this system. Instead, note down the ships “System Damage” threshold, which is equal to one-third its original HP, rounded down.
Execute steps 1-4 of starship combat normally, as written on page 68 of the corebook. In step 5, however, note whether the ship has taken more damage than its System Damage threshold.
A ship that has taken damage equal to or less than its System Damage threshold suffers no ill effect. Once a ship has sustained damage exceeding its System Damage threshold, one of its systems is badly damaged or destroyed. Roll a System Failure roll consisting of 2D6 to determine which system. Apply a -1 to this roll for each previously damaged system. If the targeted system is already completely destroyed, go down one step in the table and destroy that system instead.
After System Failure is resolved, subtract the System Damage threshold from the damage taken, rolling System Failure again if necessary until the damage taken is lower than the System Damage threshold. Very damaging attacks can spill over and take out multiple systems in one go.
Targeting or Rerouting Systems
Thanks to the complex interplay of power systems, feedback loops, and systems being integrated through the ship, a skilled mechanic can often save a failing system at the cost of another. If the ship has a mechanic on board, he or she may make a Mechanics roll, difficulty 7. This difficulty increases by +1 for each system already disabled. If the roll succeeds, the Mechanic may modify the System Failure roll by up to two points, higher or lower as she wishes.
A ship’s gunner can attempt to aim for specific targets on the enemy ship. This option replaces the “fire to disable” maneuver. Damage is halved, but if the ship suffers enough damage to exceed System Damage threshold in this shot, the enemy gunner may modify the System Failure roll by up to two points, higher or lower as she wishes. A ship’s mechanic can try to reroute the damage, but a Mechanics roll against specific targeting is made at a +2 difficulty.
Comment: It is strategic to randomly fire at a ship until it is near its System Threshold, and only then aim for a specific system. This is consistent with the game’s original rules for firing to disable, where doing so does not become advisable until the ship is nearly destroyed. Note however that it is entirely possible for a very good damage roll to unintentionally exceed System Threshold, wrecking a different system than intended, so pulling your punches from the start can still be advisable if you intend to take down a ship gently.
The System Failure Roll
0 or less) Power Core. Destruction of the power core causes the immediate destruction of the ship with all hands. It is under these rules not possible to power down the power core “retroactively” if it is destroyed.
1) Spike Drive. Destruction of the spike drive is often as catastrophic as a power core failure. Roll 1d6. If the result is equal to or lower than the current occupied phase, a catastrophic gravitational surge overwhelms the ship, and it is ripped apart by the phase tides, destroyed with all hands. Otherwise, the spike drive simply causes a power surge, knocking out all power on board. Treat this as a “power systems” shutdown.
2) Power Systems. Destruction of the power systems causes them to shut down, leaving the entire ship unpowered and helpless.
3) Propulsion. If the ship’s propulsion is destroyed, the massive explosion of the fuel supply causes the ship to immediately suffer another Systems Failure roll immediately. The explosion of the propulsion also leaves the ship unable to move, empties all fuel reserves, and knocks it away in a random direction. This is usually meaningless in open-space combat as the enemy can easily pursue it, but if the ship is near to a planet, it may cause uncontrolled descent at the GM’s discretion.
4) Fuel Containers. The ship’s fuel containers are hit but do not explode, exposed to vacuum before they have time to fully ignite. They harmlessly dissipate almost instantly, leaving the ship unable to move with empty fuel reserves. Piloting maneuvers are no longer possible, but the ship’s pilot may as a last-ditch effort set a course towards help by rolling a Pilot roll (difficulty 7) burning up the last fuel before it escapes. From there on, the ship floats helplessly in a straight line.
5) Life Support. The ship’s atmospheric freshers and temperature regulation are destroyed. In areas where the hull is intact, it is possible to survive for a time depending on the ship’s class – 1d6 minutes for fighters, 1d6 hours for frigates and cruisers, and 1d6 days for capital ships. If the ship contains less than half its max crew, double this time. Once this time expires without the life support system being repaired, the interior of the ship is no longer habitable, and characters must rely on vac suits to survive.
6) Weapons. One weapon is disabled, and cannot be used until repaired. if there are no more weapons left, treat this system as destroyed and go down one step.
7) Hull Breach. The hull is badly damaged, but in some non-vital area. Most ships are equipped with internal clamps to seal off the damaged area; the ship’s non-weapon fittings become inaccessible to persons without a vac suit, but assuming they are properly strapped down, all lockers shut, et cetera, they are not damaged. Fittings can still be remotely accessed with a computer if appropriate – so, for example, while the extended life support cannot be reached by the ship’s mechanic unless he wears a vac suit, it remains powered and responsive to commands. If the ship suffers a second hull breach, its internal clamps fail and the crew usually dies unless they are appropriately protected (strapped down and wearing vac suits). After two hull breaches have occurred, treat the hull as “destroyed” if it is rolled again.
8) Computers. The ship’s computers are badly damaged, and treated as destroyed. This shuts down sensors and makes spike drive navigation impossible. Weapons usually run off their own computer systems, and are unaffected; similarly, the pilot can rely on simple readings to continue navigating, albeit at a -2 penalty. All other Computer-based tasks on board become impossible unless they depend on independent handheld items. Even handheld items from the ship’s locker are useless, as they rely on communication with the ship’s server.
9) Inertial Dampening. The ship’s artificial gravity and inertial dampeners are destroyed. The interior of the ship becomes weightless if it wasn’t already, and the inertial dampening fails. Any Pilot maneuvers cause any loose objects or people aboard to be thrown about mercilessly in merciless accordance with Newton’s Laws, dealing 1d6 damage per Speed of the ship unless a successful Evasion save is made.
10) Sensors. External sensors are destroyed. Navigation and piloting rolls suffer a -2 penalty, but are otherwise not affected. If the ship’s computers are already destroyed, this has no immediate effect; it merely destroys the non-functional sensors, forcing the crew to replace them as well as the computers assuming they survive. Weapons come with their own sensors, and are not affected.
11) Fittings. Somehow, a random ship’s fitting is destroyed. A ship’s locker might be knocked off the wall, its contents smashed and scattered, or the extended life support might fail leaving only “regular” amounts of life support. These failures are normally non-critical, though their loss can impair life aboard under certain circumstances. If anyone is so unfortunate as to be occupying the given fitting (for example, a destroyed drop pod) the GM may allow them an Evasion roll to escape. Failure usually means death. Fittings can only be hit once in a given combat; treat this system as “destroyed” once hit.
12 or greater) Cosmetic damage. Through sheer dumb luck, the shot merely scrapes the hull or blasts away a non-critical sensor array, leaving the ship scarred but fully functional. A ship can only suffer cosmetic damage once in a given fight; treat this system as “destroyed” once the result has been rolled once.
Lady Claw is trying to escape her collapsing space station in a small fighter, but a rebel free merchant picks up the chase. Lady Claw’s fighter has 5 armor and a System Damage threshold of 2 – enough that even a small amount of damage threatens the frail fighter’s systems.
The rebel ship catches up with Lady Claw, and her evasive actions fail. Fortunately, this is her private fighter equipped with an ultra-rare pretech Polyspectral MES Beam. The rebel ship, by contrast, is armed only with a Multifocal Laser and a Sandthrower.
(For simplicity, we’ll ignore rules about ship phase in this example, though they still apply)
Lady Claw fires her MES beam at the freighter and rolls a 20 – an automatic hit! The powerful pretech weapon is armor-piercing to the degree that it entirely ignores the enemy armor! Meanwhile, the freighter’s gunner fires the multifocal laser, also an armor-piercing weapon.The gunner misses, however, rolling only a pitiable 2. The other gunner fires the Sandthrower, and rolls 16 plus the Figher’s AC of 4 and the gunner’s skill – the result is more than 20, enough for a hit. As it’s a flak weapon, it does double damage to small ships!
Both ships now roll damage. Lady Claw rolls 7 damage, entirely ignoring armor. The freighter’s Sandthrower rolls 6 damage, doubled for a total of 12! Lady Claw’s armored fighter subtracts 5 damage from this leaving 7 damage to her ship as well.
Lady Claw’s tiny Figher only has a Damage Threshold of 2. Since she’s suffered 7 damage, she must roll three times on the System Failure table before the damage is reduced beneath her ship’s threshold. She has no mechanic and cannot change the result. The first System Failure roll is a 12 – a lucky grazing blow! The second roll turns up a 7, but since Lady Claw already has one damaged system, 1 is subtracted from this. The resulting 6 takes out her only weapon! Finally, on her third roll, Lady Claw rolls a 5. Now she has two destroyed systems, so the result is reduced by 2. Her propulsion system is hit! The explosion forces a fourth roll, which turns up 11-3, destroying her computers as well – and she goes spiraling towards a nearby planet, out of control.
The Freighter has a System Damage threshold of 6, so it rolls once on the System Failure table and thereafter reduces its total damage taken by 6. This leaves it with 1 damage suffered, less than its System Damage threshold, so it needn’t roll again. Bad luck, however – they roll a 2, a disastrous result! Their mechanic intervenes, succeeding on the roll and successfully averting a power shutdown, but he’s forced to change the result to 4, and dump the fuel reserves. With a last-ditch effort, the freighter’s pilot turns around the ship and heads back for safety. They all saw the explosion – surely Lady Claw couldn’t have survived…