Archive for the Other vector movemet systems Category

Version 3.4.3 update

Posted in Boardgames, Design system, Intercept, Other vector movemet systems, Traveller on December 11, 2016 by Mr Backman

Board and counters

Vesta acquisition. In response to the verbal from the autopilot, Dieter Ulans flipped his datavisor in front of his eyes and prepared to take direct command of the massive ring of lasers and reaction engines that was Hercules. He hit the juicer button and felt the rush as the drugs began to wash into his veins. “Com’monn jockey juice!” he whispered and then began to croon: “All my thoughts of you, you, you — all that I’ve sought is you, you, you.” The tiny green symbols on the datavisor began to zip past his eyes at an increasing speed.

From the rulebook to Battlefleet Mars 1977 – Essentially the Expanse setting but 39 years before it aired.


There are lots of changes all over the rules, too many to mention. Sections have also been rewritten, gotten new or updated illustrations or have been rearranged, to clarify and simplify without actually changing too much.

As always, read the front page to get a feel how the game works. Then, read pages 2-3 which cover tasks and initiative, very important to grasp. From then on, simply start playing a turn and read as the turn progresses, the rules are written in turn sequence order.

You can download it all here, as usual, with the updated designs, maps etc.


The task system has gotten a facelift and a slight change to what Miss margins give what result. All tasks are now highlighted in red in the table columns to make them easier to find, they are also duplicated on the four reference pages at the back. All degrees of success or failure are now three points wide:

  • Very Good You rolled at least 6 points above the target number.
  • Good You rolled 3-5 above the target number
  • Fair You rolled 0-2 above the target number
  • Miss You missed by 1-3
  • Bad You missed by 4-6
  • Very Bad You missed by 6 or more 


The movement rules are basically the same as before but rewritten and clarified with step by step illustrations on how movement is performed. The section on plotting has also been clarified and with a detailed example illustration showing all aspects of plotting.


Fractional thrust Ships don’t come with Thrust in increments of whole Gs, fractions in increments of 0.25 Gs allow the ship an extra G on certain turns of every group of four turns. The mapsheet holds helpers for this and there is also check-boxes for fractional thrust, loaded and unloaded, on the ship Datacard too. All ready-made designs have these already filled in for you. A ship with 1.25 Gs of thrust would thrust 2 G on turn 1 and 1 G on turns 2-4, 2.5 Gs of thrust would thrust 3 G on turn 1 and 3 and 2 G on turns 2 and 4. A ship with 0.75 Gs of thrust would thrust 1 G on turns 1, 2 and 3 but cannot thrust on turn 4 of every group of 4 turns.

Free traderDatacard fractional thrusts

As damage to Thrust and Power affected how many Gs a ship could thrust this has been changed too, so you don’t have to recalculate what fractions to use as you get damage. Now Thrust and Power damage affects how many turns in a row you are allowed to thrust. All, 2 turns , 1 turn or not at all for No damage, Light, Severe or Critical damage. Plotting rules teach you to draw a circle around your ship whenever it drifts and thus reset the clock on thrust.


The fundamentals of the sensor rules remain the same, just clarifications and better examples. The only changes I can think of is that you no longer can use your Visual/IR and Radar sensors when popped in. On the other hand, ships may now pop in at any time during a turn as long as they haven’t used their weapons yet. Ships lose any tracked enemies and any launched missiles when popping in but as you know the vector and position on your targets when they were tracked reacquiring them should be fairly easy.

Oh, one more thing. Intercept now allow 2×2 scans, 2×2 square scans are +2 (+4 for radar), 2×2 boxes are -2 (-4 for radar). I didn’t allow them before because they didn’t have a clear center but showing where your scan is located should pose no problem anyway.

Map coordinate legend

The plotting rules now teached how to refer to boxes and sqaures on the map, using the legends on the map. To efer to the top left box of the map, say “Ay-one”, to refer to the bottom left square of the box where the latrge planet is in say “Dee-six one-five”. Always use column-then-row for the boxes followed by column-then-row for the individual squares.


The combat section has been rewritten and lots of die modifiers have been removed or baked into other rules. How much a ship thrusts no longer affect how hard they are to hit, we simply give a +2 DM on attacks, and defense when  drifting.

Underpower When a ship didn’t have enough power to use all their weapons when thrusting or drifting we previously used two DMs, peculiarly placed low on the Datacard and was often forgotten (I admit to cobbling it in wherever there was room).

Freetrader underpower ratings

Now, Underpower is one of All+, All, 2 turns, 1 turn, No fire, ships have separate Underpower ratings for Thrusting, Drifting or Jump prepping (more on that in the optional hyperspace rules). When a ship has Severe damage in its power location its Underpower rating is one level worse, All+ becomes All, All becomes 2 turns and so on.


Damage has changed considerably in this version. Ships now have only one DAB (Damage ABsorption) rating for the entire ship instead of one per location, ARM (for ARMour) is still per location and sometime even have two values, popped out / popped in for Surface damage, full power / silent running for high powered power locations representing their vulnerable heat radiators.

Penetration and Damage tables

How do we handle different damage at different locations then? We have three separate columns on the damage table, one for Hull, one for Crew, Core and Power and one column for Surface and Thrust.

Aerobraking & landing

I seem to rewrite the aerobraking and landing rules once every two weeks or so but now I have something that I feel I’m done with as it is fairly simple yet contains everything I want it to do. Docking and ramming has been moved to the optional rules as they tend to be used more rarely. I have increased the safe speeds for aerobraking somewhat so they become more useful. New illustrations and two examples help clarify things. there is even a little section dealing with your ships signatures when landed and how your sensors work through and atmosphere. Yeah, landing on the day side of a planet with atmosphere will make you harder to scan but your Visual/IR sensors will be blind from the bright atmosphere.

Optional rules

Campaign rules If you want to play a series of Intercept scenarios and have your crews and/or entire navy improving is skill from experience this is for you. The rules merely deal with how to track skill improvements but also skill loss from crew damage. There are also some bare bone outlines of scenarios to help you with ideas. This system is what we use at work when playing and interconnected series of space fights.

Redlining Have you ever wanted to pull all the safeties as captain Phillips did when Somali pirates tried to intercept him, or yell at your engineer ordering him to once again do the impossible? In other words, have you ever wanted to redline your engines?

You decide if you want a 50% boost to your thrust this turn or doubling it for a turn, the latter is of course more dangerous. There is a considerable likelihood that your thrust location will get a CD (Continuing Damage) ie ‘fire in the engine room!’ and you may even risk damaging your engine. Redlining, as well as powering up from silent running and the usual jury-rigging of battle damage is done by your trusty Repair Crew.

Jump distances for planets and asteroids

Hyperspace The rpg Traveller has a faster than light system that works by travelling far away from any planet, jumping into hyperspace, spending about a week there and exiting somewhere else parsecs away from where you started. I have shrunk how far one must travel to safely jump to fit planet and safe jump onto an Intercept mapsheet. There are some fairly detailed rules about how to jump, fuel use, astrogation, misjumps etc and where you will end up. In my system, all jumps have you end up somewhere, near a gas giant, planet or asteroid, even when you misjumped into an ’empty’ parsec hex in the original Traveller.

If you are playing a Traveller campaign I suggest you not only replace the space combat and starship movement rules with Intercept, replace the hyperspace rule too.

Design system

There are tons of changes to the design system too. Most importantly I think you get all the important design spec data in one place. As shown by this part from the Free trader design spreadsheet available in both InterceptBundle and Designs.

Ship stats for the Freetrader

Three little orange dots appeared on the screen. Look at him — blowing out decoys even though he knows we’re out of maneuver — that Kolnichok, grinned Dieter. So which one is you, Joey, and which are the aluminum balloons? (Seven dots grew on the screen, all had slightly different vectors.) Now you know my heater can take you in one flash and you also know that one zap is all I’m going to get. And if I take it you’ve got a perfect excuse to blow me up for the honor of the company rather than recapture valuable property for the accountants. So what’s it going to be? I think you shot off too many balloons too early Joey — cause the other ones aren’t making the course correction you just did. Ain’t that you, Joe?

Ulans squinted and tapped his foot.

From the rulebook to Battlefleet Mars 1977 – notice the green grid tactical maps where one could play out space battles with vector movement, in 3D no less, in 1977!


The contents of SPIs Battlefleet Mars boardgame from 1977.

Gravity in boardgames

Posted in Boardgames, Design system, Intercept, Other vector movemet systems, Scenarios on May 13, 2010 by Mr Backman



Space combat games are typically played on black hexgrids with no terrain features at all. Some games add asteroid fields, planets, nebulas, electric storms etc and some even try to incorporate the gravity field around planets. This is at least something we know, real planets do have gravity fields around them and climbing up the gravity well takes serious effort; just look at how big the Saturn V needed to be in order to send three guys to the moon and back.

What can we say about gravity then? Well, it pulls you back toward planets, a ship can remain indefinitely in orbit without thrusting, the higher above the planet a ship orbits the longer it takes; 1.5 hours in low orbit, 24 hours in Clarke orbit and a whole month per lap when you are as far away as the moon. We also know that if a ship has enough speed it can escape the gravity of a planet, this speed is called escape velocity for obvious reasons. Orbits don’t have to be circular either, they can be elliptical with one part getting real close to the planet and the other part taking it back further out, these orbits are also stable and require no thrust to maintain.

Prior examples

The first boardgame I came across that used vector movement was also the first that tried to depict gravity in a sensible manner, that game was Mayday. Mayday borrowed its gravity rules from Triplanetary and the mechanics where simple: If your vector, including its endpoint but excluding its startpoint, intersected one or more hex adjacent to a planet its future position would be affected. Another game with gravity rules was a game called Orbit war that was published in the Space gamer and then became a full blown boardgame.

Intercept version

In Intercept we want to do more than just being in orbit or not. Having several stable orbits with different periods allow us to model low tech orbital warfare with limited endurance fission/fusion rockets and spotting limited by the horizon. We can do elliptical orbits but that is something that just happen to work, free chrome one could say.

How do you do gravity in Intercept then? If your ship is inside a planet’s gravity well (6 squares for Earth) check what arc of the
planet you are in and adjust your drift in the direction of your current position towards the planet. Yes, gravity pull is based on the
position of your ship versus the planet but applied on the drift of your ship. If your ship is on the planet itself you do not adjust for
gravity (what direction would that be?).

That is all folks; if the ship is inside the gravity well but not on the planet you note the direction towards the planet and move your drift in that direction.

Scenario: Fission duel

This is a simple scenario with two equal ships battling it out in orbit above a planet. the ships start in the same orbit on opposite sides of the planet knowing where the opponent is but they cannot track him because the planet blocks LOS. The ships are 1G fission thrusters with 8 turns of thrust endurance and they are armed with a single small missile turret. You must carefully maneuver your ship close enough for your missiles 2G range single turn range. The ship has a crew of two; 1 pilot and 1 gunner/sensor op, there is no repair crew so there can be no repairs. Use the orbit from the image, ship A starts at x=0, y=-1, ship B starts at x=0, y=1 with the drift positions as shown. As I said earlier, this scenario is especially suited for deterministic play.

Gentlemen, start your fission drives, let the duel commence!

Major victory: Your opponent is a mission kill (incapable of firing and incapable of maneuvering) and you manage to land on the planet.

Minor victory: Your opponent is a mission kill and you are not.

Draw: Both ships incapable of maneuvering  and in such orbits that they will never get within 2G of a missile shot.

Make your own TL 8 Fission thruster equipped ships, equal or custom designed by each player. 100 MCr each is my suggestion for price.

The vector on the map or not?

Posted in Other vector movemet systems on March 29, 2010 by Mr Backman

You want to display the ships current position and perhaps in what direction it is facing, you also need to display the speed and direction of the ship. The basic system of having a past, a present and a future marker to depict the position, vector and acceleration is in my opinion the most elegant as it puts so much information on the gameboard. The GDW boardgames Mayday and Battlerider used this system but there other ways of depicting the vectors.

You can have one piece showing the position and facing of your ship and use other means for depicting its velocity (or vector). In grid based systems such as the tactical space combat in Battlefleet Mars you used three numbered chits to depict vector length, one for each of the three dimensions. In Brilliant lances they used a 12 point system for facing (you were either facing a hexside or a hexedge) and two counters on your status display for the direction and length of the vector. The system hardest to grasp of all vector system I’ve tried is the one used in Attack vector: All other vector systems I am aware of depict one unit of thrust as one unit of speed added, ie if you thrust one unit you move one unit and add one unit of speed. This is a simplification as the ship is thrusting during the entire turn so one unit of thrust would add one to speed but only one half to position. Attack vector does this correctly and they also consider the fact that a turning ship that thrusts will spread out the thrust from the starting direction to the ending direction. These effects are real and by taking them into account one could argue that Attack Vector is the most realistic vector movement boardgame there is. There are however other aspects of space combat that I think Attack Vector fails in namely the fact that ship commanders should know how to fly their ships and what their enemies are capable of. Playing several games of Attack vector we all felt like drunken monkeys trying to steer our ship by guesswork alone. As the game offers no features of the mapboard itself such as planetary shadows, sun directions, whiteouts from nuclear explosions etc the entire game boils down to understanding how ships move.

If the vectors aren’t displayed on the mapboard you must rely on looking at the counters and doing some head math to predict where your enemy is going, the gameplay becomes guessing how the enemy ships moves. In my opinion you should put as much information unto the map itself as possible to help with the gameplay. Why do we have mapboards at all? Showing the ships position on the map helps the players decide how to maneuver but in vector movement one could argue that the vector information is even more important to show on the map. We could have games where ship position, ship orientation and ship vector were all tracked on a status board with no map at all. We would no longer need to bother mapboard edges etc but everyone would agree that the game would be really hard to play. If we track position on the board we should track vectors there too as we want the players to win by tactical choices rather then knowledge of the rules.

Put the vector information back on the mapboard and let the players concentrate on playing the game!