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Mongoose Traveller SRD


If the combatants are all unprepared for combat, then each rolls 2d6 and adds their Dexterity DM to determine starting Initiative. Initiative determines the order that characters act in, but it can also be spent to react to events. If some of the combatants are ready for combat and some are not, such as in an ambush, the prepared characters are considered to get an automatic 12 on their roll, giving them an Initiative of 12 + Dexterity DM.

Characters who have the Tactics skill may make a Tactics check and add the Effect of this check to the Initiative of everyone in their unit.

The Combat Round

Each combat round lasts around six seconds of game time. In a combat round each character gets a minor action and a significant action. Actions are taken in descending order of Initiative. If two characters have the same Initiative, the character with the highest Dexterity goes first. If they are still tied, then characters act simultaneously. When a character acts, he takes all his actions at once.

Once everyone has acted a combat round is over and a new round begins. Initiative is not re-rolled but is dynamic, and may be adjusted up and down by actions taken during a round.

Dynamic Initiative

During the course of a round a character’s Initiative score may be changed by reactions, recoil and hastening. Any changes affect your Initiative for one round only – either the current round if you have yet to act or the following round if you have acted already. Reactions reduce your Initiative in order to allow you to defend yourself from attacks. Recoil slows you down if you are using a weapon heavier than you can handle. Hastening your action lets you act sooner but at a penalty to your roll.

At the start of each combat round a character may declare that he is acting hastily. This gives him a +2 bonus to his Initiative for that round only but all his actions receive a –1 DM. A character can only hasten once.

Minor Actions (top)


The character moves up to six metres. Difficult terrain, such as rubble, mud or thick underbrush can halve a character’s movement, allowing him to move only three metres per movement action. Crouching also halves movement.

Changing Stance

A character can change to any one of the three stances – prone, crouched or standing – as a minor action.

Drawing and Reloading

The time taken to draw a weapon depends on its size and ease of use. The number of minor actions to ready or reload a weapon is listed in the description of each weapon. Most weapons take one minor action to draw and another minor action to reload, but some weapons are especially fast or slow.


A character who spends a minor action aiming at a target gets a +1 DM to his next attack on the target, as long as the character does nothing except aim until he makes his attack. A character may spend multiple actions on aiming, gaining a maximum aiming DM of +6 if he spends six minor actions on aiming.


The Referee may permit a character to perform a skill check or other action as a minor action if the use of the skill does not require the character’s full attention or complex physical actions.

Significant Actions (top)

Minor Actions

A character can take two minor actions instead of a significant action.


A character may make a skill check or do something else as a significant action when such an action requires the character’s full attention, concentration, complicated physical actions or some combination thereof.


The most common significant action is an attack. The basic attack action is trying to injure a foe with a melee attack or a ranged weapon. The attacker declares his target, and the foe may choose to react. The attacker then makes a skill check, and if successful, deals damage to his target. As with any other skill check, the standard roll for success is 8+.

The standard skill checks used in making an attack are:

Melee Attack = 2d6 + Melee (appropriate specialty) + Strength or Dexterity DM (attacker’s choice)

Shooting Attack = 2d6 + Gun Combat (appropriate specialty) or Heavy Weapons (appropriate specialty) + Dexterity DM

Thrown Attack = 2d6 + Athletics (co-ordination) + Dexterity DM

Common Modifiers to Attacks
Bonuses  Penalties 
Aiming+1 per Aim action Cover–0 to –6
Laser Sight+1 if aiming Movement–1 for every 10 full metres of target movement
Intelligent Weapon+1 if total DM is within the program’s tolerance Target Dodges (Reaction)–1
 Environmental Effects–1 to –2
 Range–0 to –6
 Target Stance–2 if attacking a prone target at Medium or greater range if attacking a prone target at Personal range
 Target Parries (Reaction)-Defender’s Melee skill

Recoil and Heft

When you make an attack, compare your Strength DM to the Recoil rating of the weapon you are using. If your Strength DM is lower then the difference is applied to your initiative next round. Melee weapons have a rating called Heft which works in exactly the same way.

When firing automatic weapons in burst mode, increase Recoil by 1. When firing them on full auto increase Recoil by half the Auto score.

Reactions (top)

The more time a character spends reacting, the longer it will be until he acts himself. Each reaction lowers Initiative by 2 and applies a –1 DM to all skill checks until the following round. There is no limit to how many times a character can react in a round but a character can only react once to each attack and the penalties from reacting are cumulative.

A character can only react to attacks that he is aware of.


A character who is being attacked may dodge, giving his attacker a –1 DM and giving himself a –1 DM on all skill checks until the next round. If the character is in cover or has an obstruction to duck or dodge behind, the DM to hit him is increased to –2.


A character who is being attacked in melee can parry, applying his Melee skill as a negative DM equal to the attack roll. A parrying character also has a –1 DM on all skill checks until the next round.

Other Actions (top)

Free Actions

Some actions are so fast they do not even qualify as a minor action – shouting a warning, pushing a button, checking your watch, and so on. A character can perform as many of these free actions as he likes in a turn, although if he performs several the Referee may require him to spend a minor or even a significant action on his various tasks.

Extended Actions

Some skill checks will take longer than a single combat round to complete. Make a Timing roll for the task and then work out how many six second combat rounds it will take to complete. A character engaging in an extended action cannot do anything else but can abandon their action at any time and return to the normal Initiative order. A character who is hit by an attack while undertaking an extended action must make an 8+ roll using the skill in question with a negative DM equal to the amount of damage the attack causes (after armour). Failure indicates that this round’s work does not count towards the completion of the task. Failure by six or more (an Exceptional Failure) ruins the task and the character must start again.


A character does not have to act when his turn comes up in the Initiative order. He may act at any later point during the round, even interrupting another’s actions to do so. When he acts, his Initiative is set to the count on which he acted. If the character has not acted by the end of the round he may choose to act first in the next round, effectively giving up his actions in the previous round in exchange for an Initiative advantage. His new Initiative is set to one higher than that of the current first person in the order. When multiple characters are delaying and all wish to act first in the following round, their Initiatives are all set to the same score and they act in Dexterity order as normal.

Special Considerations (top)

Automatic Weapons

Automatic weapons – any with a number listed in the Auto column are capable of three fire modes: single-shot, burst, and auto-fire.

  • When using single shots, make attacks as normal.
  • When using burst fire, add the Auto value to the damage. Burst fire uses a number of rounds equal to the Auto rating.
  • When using auto-fire, roll a number of dice equal to the Auto rating of the weapon and sort them into pairs as you wish. Each pair is an attack. Auto-fire attacks can be allocated to as many different targets as you have attacks provided all the targets are within six metres of each other. Auto-fire attacks cannot benefit from a skill any higher than level 1. Weapon skills of 2 or higher only count as 1 when making auto-fire attacks. Auto-fire uses a number of rounds equal to 3 x the Auto rating.

Battlefield Comms

Communications technology is a vital part of the battlefield. If a character is not in communication with the rest of his unit and his commander, then he cannot benefit from Tactics or Leadership. Characters who benefitted from Tactics at the start of combat and are later cut off from their commander have their Initiative lowered by the same amount it was boosted at the start of combat. Unlike other Initiative modifications, this lasts until combat ends or communication is re-established. There are several methods of communication:

  • Direct: This covers hand signals and verbal communications.
  • Hardlinks: Hardlinks are wires or other physical connections, and cannot be jammed.
  • Radio: Radio communications allow communications as long as the radio signal can get through – they can be jammed or blocked by local conditions.
  • Laser: Two characters with tight beam lasers are in communication as long as line of sight exists between a character and another friendly laser-comm equipped character.
  • Masers: These work just like lasers, but can cut through smoke and aerosols.
  • Meson: Meson communicators cannot be jammed or blocked, but cannot be used while a character is moving.

Battlefield Sensors

There are several types of sensors.

  • Bioscanner: Bioscanner ‘sniffers’ detect airborne pathogens and hazardous chemicals.
  • Infra-Red (Heat):Infra-red sensors detect warm bodies, and negate concealment from smoke and soft cover, but can be jammed by strong heat sources.
  • Densitometer: An outgrowth of gravitic technology, a densitometer can scan an area and plot variable densities, effectively creating a three-dimensional map of all objects.
  • Electromagnetic Detectors: These sensors can detect unshielded high-power electrical devices, such as gauss weapons or transmitters.
  • Laser-Assisted Targeting: A low-powered laser is reflected off the target, giving targeting data to the firer.
  • Light Intensification: Light intensification technology magnifies visible light, negating the penalties for darkness or low light.
  • Motion Sensors: Can detect motion within range.
  • Neural Activity Sensor: A combination of highly sensitive EM-detectors and psionic theory, NAS detectors pick up on the brain activity of living beings and classifies them according to amount and complexity, giving a rough idea of the intelligence of subjects.

Certain battlefield conditions affect ranged attacks:

  • Darkness: Low light gives a –1 DM to ranged attacks. Complete darkness gives a –4 DM. Light penalties can be avoided by using sensors to target instead of the naked eye.
  • Smoke or Fog: Smoke gives a –1 DM to ranged attacks by obscuring the target; especially thick and impenetrable smoke gives a –2 DM. These penalties are doubled for laser weapons.
  • Extreme Weather: Driving wind, rain, snowstorms and so forth give a –1 DM to ranged attacks from poor visibility and a –1 DM to ranged attacks from environmental interference. Sensors can be used to avoid the visibility penalty.


Any sort of low wall, undergrowth, convenient rocks or other objects can serve as cover. Attacks made on characters who are behind cover suffer the negative cover DM on the table below. Crouching or prone targets (see overleaf) can claim cover one step higher on the table. If a character in full cover is crouching or prone they are impossible to hit but cannot return fire.

CoverCover DM
1/4 (undergrowth, small rock, corner of a building)–0
1/2 (thick forest, low wall, crate)–1
3/4 (jungle, trench, reinforced position)–2
Full (pillbox)–4


Grenades, rockets and other explosives affect an area. A character caught in an explosion may dodge at the usual Initiative cost. A character who dodges an explosion may reduce the damage by 1d6 if he just dodges or by half if he dives for cover. A character who dives for cover ends up prone and loses his next significant action.

Firing into Combat

If a character is firing a weapon at a target who is at Personal range to another combatant, then the attack suffers a –2 DM. If the attack misses, roll 1d6. On a 4+, the attack hits the nearest other combatant to the original target.


A character can attempt to wrestle or grab another person instead of hitting him. The attacker must move to Personal range and beat his target in an opposed Melee (unarmed) check. If he wins, he may do any one of the following:

  • Knock his opponent prone.
  • Disarm his opponent. If he succeeds by 6+ he can take the weapon away; otherwise it ends up on the floor.
  • Throw his opponent up to three metres for 1d6 damage.
  • Inflict damage equal to 2 + the Effect.
  • Escape the grapple and move away (as if with a normal movement action).
  • Continue the grapple with no other effects.
  • Drag his opponent up to three metres.

Throwing an opponent always ends the grapple. With any other option the winner can choose to end or continue the grapple as he sees fit. A character in a grapple cannot move or do anything other than make opposed Melee checks. Each time an opposed check is made the winner can choose an option from the above list.


Personal combat is divided into a series of range bands:

RangeDistance to TargetSquares to Target
PersonalLess than 1.5 metres0 (combatants are in the same square)
Close1.5 to 3 metres1 to 2 squares
Short3 to 12 metres3 to 8 squares
Medium12 to 50 metres9 to 34 squares
Long51 metres to 250 metres35 to 166 squares
Very Long251 metres to 500 metres167 to 334 squares
Distant501 metres+334 squares+


A character can be standing, crouched or prone.

A standing character uses the normal rules. A crouching character moves at half speed but can make better use of cover. If a crouching character is in cover, consider it one row lower on the Cover.

A prone character cannot make melee attacks or dodge. He may make improved use of cover like a crouching character and he may still parry melee attacks. All ranged attacks targeting him suffer a –2 DM penalty. At Close range, the penalty is reduced to +0; a prone character being attacked at Personal range grants a +2 DM to attacks against him.

Tactics and Leadership

The Tactics skill can be used to give an Initiative bonus to a whole unit at the start of combat. The unit commander may make a Tactics check, and everyone in the unit may increase their Initiative by the Effect of the check.

The Leadership skill can be used to increase another character’s Initiative. The character with Leadership makes a Leadership check, and the target character’s Initiative is increased by the Effect of the check. Making a Leadership skill check is a significant action.

Thrown Weapons

There are two kinds of thrown weapons: the first kind strike a single target and do damage from the force of their impact, such as throwing knives or a thrown rock. These use the normal rules for ranged combat. The other kind of thrown weapon is a grenade or other explosive projectile that inflicts no damage from impact but typically delivers a harmful payload. The first kind of thrown weapon adds the Effect of the Athletics (co-ordination) check to its damage. The second does not.

If the attack fails the projectile scatters in a random direction for (6 + Effect) metres. This is usually only important if the projectile explodes on or after impact.


Each weapon lists the damage it inflicts as a number of d6. Add the Effect of the attack roll to this damage.

Damage is applied initially to the target’s Endurance. If a target is reduced to Endurance 0, then further damage is subtracted from the target’s Strength or Dexterity. If either Strength or Dexterity is reduced to 0, the character is unconscious and any further damage is subtracted from the remaining physical characteristic. If all three physical characteristics are reduced to 0, the character is killed.


Armour reduces damage by the value of the armour. A hit with Effect 6+ always inflicts at least one point of damage, regardless of the target’s armour.

Vehicles (top)

Combat in and on vehicles is much the same as ordinary combat. The differences are as follows:

  • Unlike people, who are mobile and manoeuvrable, careful track must be kept of which way a vehicle is facing. Vehicle-mounted weapons – and armed passengers, to a lesser extent – are restricted to certain fire arcs.
  • Vehicles are considered to move on the driver’s Initiative. The driver must spend a minor action every round to keep control of the vehicle under normal circumstances – a straight road or simple manoeuvres – or a significant action to navigate obstacles, conduct evasion or pursuit, or dodge incoming fire.
  • Attackers gain a +1 DM to hit most vehicles because of their size.

Types of Vehicles

There are two main types of vehicles: open and closed.

Closed Vehicles

  • Closed vehicles grant cover to the occupants – unless the description mentions otherwise civilian vehicles grant ½ soft cover and military vehicles full hard cover.
  • Only a few people in a closed vehicle can shoot out, depending on the number of windows or other firing ports and the internal space available. Unless the description mentions otherwise up to two people can fire into each arc from a civilian vehicle and one person in each arc in a military one.

Open Vehicles

  • Open vehicles grant no cover to the passengers.
  • Any passenger in an open vehicle can shoot (or otherwise attack) in any direction.

Vehicle-Mounted Weapons

Weapons mounted on vehicles are limited in what directions they can fire. A weapon mounted in the front arc, for example, can only fire into a 90˚ area in front of the vehicle. Weapons in turrets can fire in any direction.


When a vehicle collides with something else everything takes damage. Roll 1d6 for every 10 km/h of the vehicle’s speed (round up). This is applied as damage directly to anything hit and, if the thing struck is solid enough, also to the ramming vehicle. Any unsecured passengers in a vehicle damaged in a collision take the same damage and, if possible, are thrown three metres for every 10 km/h of speed. Secured passengers (those wearing seatbelts or something similar) are not thrown anywhere and take one quarter damage.

Vehicular Actions

These are all significant actions that the driver of a vehicle can take when his turn in the initiative order arrives.

Evasive Action

Vehicles are not typically manoeuvrable enough to dodge as a reaction. Instead, the driver may declare that he is taking evasive action when his turn arrives. He makes a skill check (skill determined by vehicle) and the Effect acts as a –DM to all attacks against the vehicle or its passengers. The Effect also acts as a –DM to any attacks made from the vehicle as well. This lasts until the driver’s next action.


A driver or pilot can manoeuvre his vehicle without making a skill check. This allows the vehicle to avoid large or obvious obstacles, to get where it is going, to move out of one fire arc of an enemy vehicle and into a different one, or to change the fire arc that a single target is in.


Deliberately driving a vehicle into someone or something requires a significant action and a successful skill check (skill determined by vehicle). Rams are affected by dodging and evasive action as normal. The Referee may grant bonuses to a ram attempt or declare it automatically successful if the target is particularly large.


With a significant action and a successful vehicle control check the driver or pilot of a vehicle can do pretty much anything it is possible to do in his vehicle – stand a car up on two wheels, perform stunning aerobatics in a jet plane, or skim a speedboat over a low sandbar. A stunt can be used to put a single target into one additional fire arc for one round, to set up some other skill check using the rules for task chains, to achieve something that would normally be difficult or impossible in your vehicle, to achieve up to three manoeuvre actions in one go, just to show off, or anything else you can imagine.


In an environment with many obstacles, such as an inner city or tight underground caverns, a driver or pilot may choose to weave his vehicle in and around the obstacles at high speed in order to evade pursuit. The driver chooses a weaving number, as low as one or as high as one per 20 km/h of speed (round up), and must then make a skill check (skill determined by vehicle) with the weaving number as a penalty on his roll. If he fails, he has woven into an obstacle and crashed. If he succeeds, any pursuers must choose a weave action when their initiative count comes up and make their skill test at the same penalty with the same consequence for failure. Alternatively, they can choose to break off pursuit and either give up or try to reacquire the target later.

Vehicle Damage

Vehicles have a Hull value and a Structure value, which measure the vehicle’s structural integrity. When Hull is reduced to 0, the vehicle starts taking damage to its internal systems. When Structure is reduced to 0, the vehicle is reduced to scrap. Vehicles also suffer damage to onboard systems as they take damage.

To determine the effects of an attack on a vehicle, first determine how much damage the vehicle suffers as normal. Many vehicles will have one or more points of armour that reduces the damage. Consult the Vehicle Damage table to determine how many ‘hits’ the vehicle suffers.

Vehicle Damage Table
0 or lessNo damage
1–3Single Hit
4–6Two Single Hits
7–9Double Hit
10–12Three Single Hits
13–15Two Single Hits, Double Hit
16–18Two Double Hits
19–21Triple Hit
22–24Triple Hit, Single Hit
25–27Triple Hit, Double Hit
28–30Triple Hit, Double Hit, Single Hit
31–33Two Triple Hits
For every extra three points+1 Single Hit
For every extra six points+1 Double Hit

Each hit is then applied to a particular location on the vehicle. Double or Triple hits count as two or three hits on the same location.

Location Table
2d6External Hit (vehicle)Internal Hit (Vehicle)Robot or Drone
3 SensorsPower PlantPower Plant
4 DrivePower PlantSensors
5 WeaponCargoWeapon or Limb
6 HullStructureHull
7 ArmourPassengersArmour
8 HullStructureHull
9 WeaponCargoWeapon or Limb
10 DriveComputersDrive
11 SensorsCockpitSensors
12 HullCockpitComputer


Reduce the vehicle or drone’s Hull by one. If a vehicle runs out of Hull, further Hull hits become hits on the same row of the Internal Damage table (if a vehicle) or Structure hits (if a robot or drone).


Reduce the vehicle or drone’s Structure by one. If a vehicle runs out of Structure, it is destroyed. If the vehicle is destroyed by an attack that reduces it to a negative Structure score it explodes, doing 4d6 damage to everyone within six metres (including the occupants) and 2d6 damage to everyone within twelve metres. The occupants of a closed vehicle cannot dodge or dive for cover from this explosion but the occupants of an open vehicle can.


Reduce the vehicle’s armour by one.


  • First Hit: Reduce movement by 10% and apply a –1 DM to all vehicle control skill checks.
  • Second Hit: Reduce movement by 25% and apply a –2 DM to all vehicle control skill checks.
  • Third Hit: Drive disabled.
  • Further drive hits count as Hull hits.


Choose a weapon or device randomly for each hit.

  • First Hit: The weapon or device suffers a –2 DM to all checks related to its operation.
  • Second Hit: The weapon or device is destroyed.
  • If no weapons remain to be destroyed, further hits on this location become Hull hits.


  • First Hit: The vehicle or drone suffers a –2 DM to all Sensors checks. For drones and robots, this also applies to Recon checks.
  • Second Hit: The sensors are destroyed, blinding the vehicle or drone.
  • Further Sensor hits count as Hull hits.

Power Plant

  • First Hit: The vehicle or drone loses one round’s worth of actions.
  • Second Hit: The vehicle or drone’s movement is reduced by 50%.
  • Third Hit: The power plant is destroyed, disabling the vehicle and inflicting 1d6 Hull hits on it.


Choose a limb randomly for each limb hit.

  • First Hit: The limb suffers a –2 DM to all checks related to its operation.
  • Second Hit: The limb is destroyed.
  • Further Limb hits count as Hull hits.


Choose a passenger randomly for any passenger hit. The passenger takes damage equal to the damage inflicted on the vehicle. If all the passengers are dead, further passenger hits become Structure hits.


Any cargo present is hit and may be destroyed. If no cargo remains, further cargo hits become Structure hits.


The pilot of the vehicle is hit, and takes damage equal to the damage inflicted on the vehicle. If the pilot is dead, further pilot hits become Structure hits.


  • First Hit: The vehicle’s computer system is disabled. A drone or robot with a disabled computer system shuts down for 1d6 rounds.
  • Second Hit: The vehicle’s computer system is destroyed. A drone or robot with no computer system is completely disabled.
  • Further Computer hits count as Structure hits.


Damage to a vehicle or drone falls into three categories – System Damage, Hull Damage, and Structure Damage.

System Damage: A damaged system can be jury-rigged back to functioning, but it will stop functioning again after 1d6 hours. Repairing a damaged system requires not only an Average skill check (Mechanic, Engineer (appropriate speciality) or Science (appropriate speciality)) taking 1–6 hours but also a source of spare parts. The spare parts can come from a scrap yard, a workshop, systems on another vehicle, or can be taken from other systems on the same vehicle. When taking spare parts from other vehicle systems, each ‘hit’ of damage provides enough spare parts to make a single repair check.

The Passengers and Cockpit systems cannot take hits to provide spare parts, although cybernetic parts might be able to provide enough spare material to repair minor damage.

A destroyed system costs 2d6 x 10% of its original cost to repair, and cannot be repaired using spare parts. It requires a full workshop and specialist materials.

Hull Damage: Hull damage can be repaired with a Mechanic check taking 1–6 hours and consumes one ‘hit’ of spare parts.

Structure Damage: Structure damage can only be repaired in a workshop and requires 10–60 hours per point of damage. It costs 20% of the base cost of the vehicle per point repaired. No skill check is required.