Combat and Tactics in Mongoose 2E
I’ve been playing Mongoose Traveller for about 4 years now, and had time to come to some conclusions both about how the combat system works, and how people actually play it – and these are not always the same thing.
These observations are based on my experience, which is to say it is limited as I haven't played that many different kinds of campaign. Please contribute your insights into how Traveller combat tactics work.
In this post, I am assuming you are doing it using a map of some sort (rather than theater of the mind, which leaves much to the Referee’s discretion), and are using the Core Rulebook rules, including the Central Supply Catalogue, but not the Field Catalogue, which would introduce additional complexity (interesting complexity, but maybe too much of it). Also, it assumes that you are not using optional rules nor house rules.
The first rule is that there really are no tactics that cover every situation. It is very much dependent on the terrain, and on the equipment and skills of the combatants. A setting such as a fancy dinner gone wrong is very different from storming an enemy hideout which is very different from a street fight by rival gangs or a military skirmish in a wild forest. Terrain, rules of engagement, and the types of gear lead to different tactics coming into play.
On D&D "tactics"
A lot of people are coming from D&D, and bring their tactics – or more accurately lack thereof – from this setting. In D&D, characters will often stand next to their opponent and trade blows until someone runs out of hitpoints. Missile or magic uses will stand back behind the fights and deliver damage in much the same way. So parties walk around in a clump. In Traveller, if you stand in the open and trade gunshots with your enemies, they may well get the worst of it if you are lucky, but win or lose, you will die sooner rather than later using that tactic, and usually have a hospital stay after every engagement – unless you have massive tech and gear overmatch in which case you can get away with just about anything (your opponents will come to expect your battledress, though, and at some point will bring an RPG to the fight).
The most effective weapons are firearms and your opponents don’t have to shoot the person in front, except in very crowded situations. Autofire, shotguns and grenades make short work of clumped up targets. The only way not to get killed is to take cover and/or shoot first, and moving around in a clump like a bunch of kindergarteners on a field trip to the zoo holding onto the teacher’s string is just asking to be machine-gunned and grenaded into a red splat on the ground. In most situations, all else being equal, you will want to spread out, take advantage of cover and concealment, and maneuver.
2d6 and probability
All pluses are not equal. With 2d6 the possible outcomes are not distributed equally. Those at the center of the range have a higher probability. The closer to 7 the higher the probability. This means that a +1 is worth a lot when the hit roll is 8+ (16.7%, or the equivalent of +3 on d20), but worth much less when it is 12+ or 4+. The outcomes at the outer edges of the range are very unlikely: a 12+ only gives a 2.7% chance of success, while a 3+ means more than 97% chance of success. Also, in contrast to other games with d20 or d100, the range is fairly narrow. +1 or -1 is a big deal.
The basic “to hit” role is of 8+ gives a person with Level-0 competence with a weapon a 41.66% chance to hit an opponent. Level-1 competence (or taking a minor action to aim) raises this probability to 58.33%, or Level-1 and aiming makes it 72.22%. A typical firearm such as the Autopistol will do an average of 8 damage, or max 15 points, up to 20 points with effect in a very lucky shot, meaning the person to shoot first has a good chance to take you out before you can do anything.
Even if the damage roll is low, every point of damage has the potential to reduce a character’s performance – by reducing endurance and then STR or DEX. An endurance of 0 will reduce what you can carry, prevent you from running far etc. And a second stat to 0 (14) damage, will put you out totally. Even this fairly mundane weapon, has a reasonable chance of leaving the character to shoot second hors de combat.
Of course, body armour changes the equation: the usual cloth for combat situation, or a Protec suit for social events reduces the autopistol’s average damage to 0 plus effect or 4 plus effect respectively, so generally the person will be able to take at least one hit without being put out of action, or maybe several. But as soon as we start to add in armour piercing or more powerful firearms, not to speak of autofire we are right back to the notion that the first shooter will usually win. An ACR on full auto with AP rounds wielded by someone with good skills can easily put 3 hits on someone. Even wearing cloth they’ll probably take upward of 30 points of damage.
Gun Combat Skill (and DEX bonuses thereto)
Gun combat skill makes it far more likely that you will take out your opponent IF YOU SHOOT FIRST. In terms of increasing your chances at hitting in normal ranges, Gun 0, 1, and 2, increase the odds of hitting massively (the closer to the median 2d6 to hit roll needed, the more a +1 or +2 influences the odds). Gun 3 or 4 is usually overkill – rolling a 2, 3, 4 or even a 5 is unlikely, although of course it is nice to have assured hits. Once we get to a 10+ or 12+ shot needed, then Gun 2, 3, or 4 starts to be more important, and/or bonuses from other sources (aiming, enhancements).
What this means is that you get diminishing returns on bonuses in short range gunfights – unless they are dodging, under cover or otherwise giving you minuses, but pluses are more important at longer ranges.
Equipment and pluses
There are a lot of different types of gear that offer too hit bonuses, and often it is not that expensive. Laser dots sights are good at short range. In general, if your gun combat skills are really high you don’t need this stuff, but with Gun Combat 1 or 2, it makes sense to look over the catalogues.
Aiming
Remember your minor action! Generally, it is a good idea to aim if you don’t have another use for that minor action. As with other pluses, it makes sense to think about where on the 2d6 probability curve you are – if the is something you might rather be doing with that minor action. You can get up to +6 for consecutive minor actions spent aiming, but who has time for that crap?
Where this really comes in handy is at long ranges, where it can negate the effects of extreme range. Together with a scope, it can give you virtually automatic hits.
How to shoot first (gear, movement and skills: Tactics, Recon, and Stealth)
In general, you will want to ambush your enemies, and not be ambushed by them. This is easier said than done, but assuming encounter is anticipated by both sides, and neither side has found the other, you will need to find them before they find you.
This means using Recon skill against Stealth. The problem is, not all characters will have these skills. If someone does have both of them, they make a good scout. They’ll need to be in advance of the rest of the group though – and be able to warn the group. Communications tech that can’t be eavesdropped on by your opponents is crucial here. Also crucial is camouflage and detection equipment appropriate to the technological context and environment. LI and thermal imaging is needed if it is dark.
The ones lacking Stealth should be significantly behind those who have it, or they will spoil the surprise.
Contrawise, it helps to have equipment to eavesdrop on your enemies.
Once the shooting starts, if at all possible never end your turn in a spot where you aren’t hidden from enemy fire, or, if there is no such spot, then a spot where you are under cover, or if that isn’t available, then under concealment. Check lines of sight on the map and think about where the enemies are, and where they might be concealed. Move from one cover to the next. If you have to check behind a corner, or through a door, for example, make sure you have movement left over when you are done – to pop back under cover, if you have to. Consider the enemies’ next moves when doing this – they can move six meters and still attack. More than that, and they will have to use their major action, which means you’ll get to shoot first.
Traveller does not have an overwatch mechanic (effectively, overwatch is holding an action until a specific target appears): if the referee house-rules one in, that will change the way you move tactically. Also, the use of suppressing fire rules from the Field Guide changes adjusts this dynamic in a similar way. However, I will write on assumption of using the normal rules. It still works similarly, but with an overwatch rule you can overwatch a spot where the enemy is concealled to cover your friend while he advances.
Tactics skill can give an advantage to initiative rolls. It can improve the ambush you set up, but is especially useful when neither side has surprise. The main challenge is remembering to use it.
Dodging, Diving for Cover and Going Prone
Dodging only works if you DEX 9 or Athletics Dex 1 or better, but if you are, and you’re being shot at, it usually makes sense to do it. If your DEX mod is -2 or -3 it is really attractive. Because you will get a -1 on your next attack from it, consider whether the attack it worth dodging – a body pistol against your combat armour might not be worth the effort. Also, if the too hit is 7 getting it to 8 is a major shift in probability but from 3 to 4 is not as much, so consider how it affects both your odds of being missed, and your prospective target’s odds of being hit by you next time around.
Diving for cover requires more consideration. The -2 is substantial, but the loss of your next attack is a big loss. Of course, this depends on what kind of attack you can really do, whether your friends are likely to finish the bad guys off anyways, and whether the attack is the sort that might blow you away completely if it hits.
Being in a prone position limits your mobility a lot. But it does give the enemy a -1 to hit you. Stacked with cover, this can be a -3. If you are in a fixed position and mean to stay there, this is a good situation.
If you don’t have the dodging skills, diving for cover and staying there in a prone position is a good option, if you are ok with being where you are.
Keep in mind when deciding whether to dodge that do to the effect rules, a -1 essentially manifests as a -1 to damage if you get hit – so not a total loss even if they hit you.
Melee
If the combat is at rifle range, you can probably forget about doing any kind of melee: you’ll be dead before you can get close.
If it is close quarters, though, and you have the skills, you might be better off closing in to melee, because once you’ve done this, the enemy can’t use his longarms against you as longarms – as clubs, yes, but no more autofire. He can use his pistol (though you can parry it). His buddies might still shoot you, though, so watch out for that.
A major difference with melee combat for skilled combatants is that skill is also relevant to defense, as well as offense, because you can apply your melee skill to “parry”. Although as a reaction, it gives a -1 to your next attack, if your skill is high, like 2 or more, it will give you a substantial advantage. Grappling also gives options to manipulate your opponent, and also to inflict damage which does not deduct for armour. High strength gives damage bonuses in addition to what you might get from your effect (meaning your strength damage essentially counts twice in melee, or dex once and strength once). If you have high melee skills it makes sense to try to go into melee when the situation arises. Rapiers and shields give +1s to parrying.
All this means you also have to watch out in close quarters situations for enemies trying to close to melee range, and if you are not prepared for a melee, try to shoot them before they get close.
I’ve been playing Mongoose Traveller for about 4 years now, and had time to come to some conclusions both about how the combat system works, and how people actually play it – and these are not always the same thing.
These observations are based on my experience, which is to say it is limited as I haven't played that many different kinds of campaign. Please contribute your insights into how Traveller combat tactics work.
In this post, I am assuming you are doing it using a map of some sort (rather than theater of the mind, which leaves much to the Referee’s discretion), and are using the Core Rulebook rules, including the Central Supply Catalogue, but not the Field Catalogue, which would introduce additional complexity (interesting complexity, but maybe too much of it). Also, it assumes that you are not using optional rules nor house rules.
The first rule is that there really are no tactics that cover every situation. It is very much dependent on the terrain, and on the equipment and skills of the combatants. A setting such as a fancy dinner gone wrong is very different from storming an enemy hideout which is very different from a street fight by rival gangs or a military skirmish in a wild forest. Terrain, rules of engagement, and the types of gear lead to different tactics coming into play.
On D&D "tactics"
A lot of people are coming from D&D, and bring their tactics – or more accurately lack thereof – from this setting. In D&D, characters will often stand next to their opponent and trade blows until someone runs out of hitpoints. Missile or magic uses will stand back behind the fights and deliver damage in much the same way. So parties walk around in a clump. In Traveller, if you stand in the open and trade gunshots with your enemies, they may well get the worst of it if you are lucky, but win or lose, you will die sooner rather than later using that tactic, and usually have a hospital stay after every engagement – unless you have massive tech and gear overmatch in which case you can get away with just about anything (your opponents will come to expect your battledress, though, and at some point will bring an RPG to the fight).
The most effective weapons are firearms and your opponents don’t have to shoot the person in front, except in very crowded situations. Autofire, shotguns and grenades make short work of clumped up targets. The only way not to get killed is to take cover and/or shoot first, and moving around in a clump like a bunch of kindergarteners on a field trip to the zoo holding onto the teacher’s string is just asking to be machine-gunned and grenaded into a red splat on the ground. In most situations, all else being equal, you will want to spread out, take advantage of cover and concealment, and maneuver.
2d6 and probability
All pluses are not equal. With 2d6 the possible outcomes are not distributed equally. Those at the center of the range have a higher probability. The closer to 7 the higher the probability. This means that a +1 is worth a lot when the hit roll is 8+ (16.7%, or the equivalent of +3 on d20), but worth much less when it is 12+ or 4+. The outcomes at the outer edges of the range are very unlikely: a 12+ only gives a 2.7% chance of success, while a 3+ means more than 97% chance of success. Also, in contrast to other games with d20 or d100, the range is fairly narrow. +1 or -1 is a big deal.
The basic “to hit” role is of 8+ gives a person with Level-0 competence with a weapon a 41.66% chance to hit an opponent. Level-1 competence (or taking a minor action to aim) raises this probability to 58.33%, or Level-1 and aiming makes it 72.22%. A typical firearm such as the Autopistol will do an average of 8 damage, or max 15 points, up to 20 points with effect in a very lucky shot, meaning the person to shoot first has a good chance to take you out before you can do anything.
Even if the damage roll is low, every point of damage has the potential to reduce a character’s performance – by reducing endurance and then STR or DEX. An endurance of 0 will reduce what you can carry, prevent you from running far etc. And a second stat to 0 (14) damage, will put you out totally. Even this fairly mundane weapon, has a reasonable chance of leaving the character to shoot second hors de combat.
Of course, body armour changes the equation: the usual cloth for combat situation, or a Protec suit for social events reduces the autopistol’s average damage to 0 plus effect or 4 plus effect respectively, so generally the person will be able to take at least one hit without being put out of action, or maybe several. But as soon as we start to add in armour piercing or more powerful firearms, not to speak of autofire we are right back to the notion that the first shooter will usually win. An ACR on full auto with AP rounds wielded by someone with good skills can easily put 3 hits on someone. Even wearing cloth they’ll probably take upward of 30 points of damage.
Gun Combat Skill (and DEX bonuses thereto)
Gun combat skill makes it far more likely that you will take out your opponent IF YOU SHOOT FIRST. In terms of increasing your chances at hitting in normal ranges, Gun 0, 1, and 2, increase the odds of hitting massively (the closer to the median 2d6 to hit roll needed, the more a +1 or +2 influences the odds). Gun 3 or 4 is usually overkill – rolling a 2, 3, 4 or even a 5 is unlikely, although of course it is nice to have assured hits. Once we get to a 10+ or 12+ shot needed, then Gun 2, 3, or 4 starts to be more important, and/or bonuses from other sources (aiming, enhancements).
What this means is that you get diminishing returns on bonuses in short range gunfights – unless they are dodging, under cover or otherwise giving you minuses, but pluses are more important at longer ranges.
Equipment and pluses
There are a lot of different types of gear that offer too hit bonuses, and often it is not that expensive. Laser dots sights are good at short range. In general, if your gun combat skills are really high you don’t need this stuff, but with Gun Combat 1 or 2, it makes sense to look over the catalogues.
Aiming
Remember your minor action! Generally, it is a good idea to aim if you don’t have another use for that minor action. As with other pluses, it makes sense to think about where on the 2d6 probability curve you are – if the is something you might rather be doing with that minor action. You can get up to +6 for consecutive minor actions spent aiming, but who has time for that crap?
Where this really comes in handy is at long ranges, where it can negate the effects of extreme range. Together with a scope, it can give you virtually automatic hits.
How to shoot first (gear, movement and skills: Tactics, Recon, and Stealth)
In general, you will want to ambush your enemies, and not be ambushed by them. This is easier said than done, but assuming encounter is anticipated by both sides, and neither side has found the other, you will need to find them before they find you.
This means using Recon skill against Stealth. The problem is, not all characters will have these skills. If someone does have both of them, they make a good scout. They’ll need to be in advance of the rest of the group though – and be able to warn the group. Communications tech that can’t be eavesdropped on by your opponents is crucial here. Also crucial is camouflage and detection equipment appropriate to the technological context and environment. LI and thermal imaging is needed if it is dark.
The ones lacking Stealth should be significantly behind those who have it, or they will spoil the surprise.
Contrawise, it helps to have equipment to eavesdrop on your enemies.
Once the shooting starts, if at all possible never end your turn in a spot where you aren’t hidden from enemy fire, or, if there is no such spot, then a spot where you are under cover, or if that isn’t available, then under concealment. Check lines of sight on the map and think about where the enemies are, and where they might be concealed. Move from one cover to the next. If you have to check behind a corner, or through a door, for example, make sure you have movement left over when you are done – to pop back under cover, if you have to. Consider the enemies’ next moves when doing this – they can move six meters and still attack. More than that, and they will have to use their major action, which means you’ll get to shoot first.
Traveller does not have an overwatch mechanic (effectively, overwatch is holding an action until a specific target appears): if the referee house-rules one in, that will change the way you move tactically. Also, the use of suppressing fire rules from the Field Guide changes adjusts this dynamic in a similar way. However, I will write on assumption of using the normal rules. It still works similarly, but with an overwatch rule you can overwatch a spot where the enemy is concealled to cover your friend while he advances.
Tactics skill can give an advantage to initiative rolls. It can improve the ambush you set up, but is especially useful when neither side has surprise. The main challenge is remembering to use it.
Dodging, Diving for Cover and Going Prone
Dodging only works if you DEX 9 or Athletics Dex 1 or better, but if you are, and you’re being shot at, it usually makes sense to do it. If your DEX mod is -2 or -3 it is really attractive. Because you will get a -1 on your next attack from it, consider whether the attack it worth dodging – a body pistol against your combat armour might not be worth the effort. Also, if the too hit is 7 getting it to 8 is a major shift in probability but from 3 to 4 is not as much, so consider how it affects both your odds of being missed, and your prospective target’s odds of being hit by you next time around.
Diving for cover requires more consideration. The -2 is substantial, but the loss of your next attack is a big loss. Of course, this depends on what kind of attack you can really do, whether your friends are likely to finish the bad guys off anyways, and whether the attack is the sort that might blow you away completely if it hits.
Being in a prone position limits your mobility a lot. But it does give the enemy a -1 to hit you. Stacked with cover, this can be a -3. If you are in a fixed position and mean to stay there, this is a good situation.
If you don’t have the dodging skills, diving for cover and staying there in a prone position is a good option, if you are ok with being where you are.
Keep in mind when deciding whether to dodge that do to the effect rules, a -1 essentially manifests as a -1 to damage if you get hit – so not a total loss even if they hit you.
Melee
If the combat is at rifle range, you can probably forget about doing any kind of melee: you’ll be dead before you can get close.
If it is close quarters, though, and you have the skills, you might be better off closing in to melee, because once you’ve done this, the enemy can’t use his longarms against you as longarms – as clubs, yes, but no more autofire. He can use his pistol (though you can parry it). His buddies might still shoot you, though, so watch out for that.
A major difference with melee combat for skilled combatants is that skill is also relevant to defense, as well as offense, because you can apply your melee skill to “parry”. Although as a reaction, it gives a -1 to your next attack, if your skill is high, like 2 or more, it will give you a substantial advantage. Grappling also gives options to manipulate your opponent, and also to inflict damage which does not deduct for armour. High strength gives damage bonuses in addition to what you might get from your effect (meaning your strength damage essentially counts twice in melee, or dex once and strength once). If you have high melee skills it makes sense to try to go into melee when the situation arises. Rapiers and shields give +1s to parrying.
All this means you also have to watch out in close quarters situations for enemies trying to close to melee range, and if you are not prepared for a melee, try to shoot them before they get close.