Monday, 28 December 2015

Game Design #63: Detection, Blinds, Vision Range - an Unwanted Mechanic?

Three very different games (2300AD Star Cruiser, Bag the Hun, and the PC game World of Warships) have me thinking about this topic of late.

The ability to effortlessly locate all enemy units in the battle is as unrealistic as the flawless co-ordination of IGOUGO but we often disregard it in the interests of "playability." Sometimes it isn't about "stealth" or "invisibility" so much as acquiring a lock/firing solution - i.e. 2300AD assumes warships are "blips" as it's hard to truly hide in space - but it's another thing to lock a ship loaded with stealth and EW countermeasures. 

There are plenty of methods to simulate the "fog of war."  Here's two common ones:

WoW/2300AD use a similar method; there is a "fixed range" at which units are spotted, depending on type.  I.e. in WoWS battleship is seen at 15km, a cruiser at 11km, and a destroyer at 7km.   This range can be extended by factors like firing weapons (+4km) or in the case of sci fi, using shields, pinging with active radar, or passive sensor capabilities.  Lightning Strike increases the "to hit" chance for every "noisy" action.   

TFL games like BtH use blinds (cards or tokens representing the unit) which are moved around on the board and are only replaced with the actual model when enemies pass a spotting roll.  Infinity uses a similar method for its stealth units.  In many games there is no blind and being "unspotted" merely gives immunity from being fired on, but that rather spoils the surprise....

It's also usual in many cases for there to be a "auto spot" range at which units are... well, automatically spotted, and then a longer range where a dice roll is required.    Some games go the "whole hog" use plotted movement but they tend to require an umpire/trustworthy opponents, AND a lot more time and complication than I care for. 

I feel activation/initiative sequences can also mesh with the concept of detection, apart from the obvious things like bonuses/better control of activation sequence for unspotted units but let's stay on topic, shall we? (Because every game design topic tends to devolve into a discussion of everyone's favourite activation method in the comments, anyway)

The problem with spotting and detection...

(a) People don't tend to "expect it."  Yes, it's weird, but how many rules (since the 80s anyway) have spotting rules by default?  I know I raise my eyebrows when I "spot" detection rules in a rulebook I am reviewing.

(b) It runs headfirst into the "gameplay depth vs complexity" conundrum.  Or to use my words, "decision points vs resolution time".  Spotting rules add another thing to do.  More measuring, more dice rolls, more modifiers - often *gasp* charts.  Like stats, charts and modifiers, it is a "victim" of the backlash against the overly fussy rules of the 80s and early 90s. In the quest for modern streamlined rules, detection rules are often seen as an unnecessary step.  Let's just skip straight to the pew-pew, shall we?

Since (a) people don't naturally expect it, putting spotting rules into a game is a bit risky, as they may perceive it as (b) adding unwanted "complexity."

So there's the challenge for a game designer:  If you think your genre needs detection rules, detection has to add enough extra tactics and decision points as to make it "worth it" to people who may not see the need for it.

How do we make detection important?
Here's a few example situations that would emphasize detection:
If weapons have a high lethality or can shoot as far as detection ranges.  So not getting spotted is important - if you have a 50% lethality (chance to die) when you are spotted - your players will care a lot about remaining stealthy.  If all weapons can shoot as far as you can see, having superior view range is, in effect, increasing your firepower/"gun range"/move:shoot ratio (perhaps allowing you a "first strike" or to "kite" your opponent; firing from beyond his visual range.)

But my game doesn't need those things?
In your Napoleonic game, muskets might only be effective to 50m - far closer than the range you can see a bunch of guys in bright red shirts.  So really, we can avoid detection rules for Napoleonics as the view range:shoot range renders it moot, right?

Well, that presumes no one was ever surprised or ambushed the Napoleonic wars.... ....and also presumes a lot about the terrain.  The troops in the French-Indian Wars would certainly beg to differ on the importance of detection and concealment.

I'm not saying detection rules are mandatory.   For example, if you do think detection had relatively minor or rare impact on your genre you could incorporate detection/ambushing into scenario design and game setup or as a special rule rather than make it an ongoing rule throughout the game.

There is a lot more to explore in this topic, but family life intrudes in the form of a bored 2-year-old....

*Detection is a vital aspect of most eras and types of warfare, but most wargames ignore it
*Detection can link with activation mechanics
*Detection does slow down gameplay; especially as most players are trained not to "expect" detection rules, designers need to ensure the extra depth makes the tradeoff worthwhile
*There are a few ways to emphasize the importance of detection; e.g. lethality/weapon range among others
*Not all games require a dedicated detection mechanic; if it has rare/minor impact a dedicated detection mechanic might not be needed and can be replaced by other things

I guess the aim of this post is to bring awareness about an oft-overlooked area.


  1. In my space battles ruleset, Pax Stellarum, ships have each a Signature, based on their size, varying from 3 to 9 (fighters have Sig 1 or 2).

    Each ship has also got a Sensors' Rating, which is usually the same accross all ships from the same faction, as it's based on that race's technology level.

    Now, you can only shoot at a target you can detect, and your detection range is equal to your Sensors' x target Signature. For instance, a Sensors 6 ship can detect a Sig 4 target (a frigate or light destroyer) at 24", while a target of Sig 6 (heavy cruiser) would be detected at a distance of 36". Thus, the bigger the target, the greater the distance you can detect it at.

    Stealth, which some scifi ships have through means of Cloaking, is represented as a negative (good) modifier to your own Sig, until you shoot on that turn.

    1. So it's sensors x sig, rather than sensors + sig of 2300AD

  2. Detection is also different to having a clear shot. The WW2 Battlegroup rules have a spotting mechanism which is different again in that after declaring your fire you then roll for each unit to see if it can get a good shot at the target. This represents good use of folds in the ground, dust, smoke etc. can be frustrating to have that guy right in your sights but then not be able to get a good shot at him!

    1. Even FoW sort of does that with "Saves" i.e. everyone shoots pretty similarly, but more experienced units get a better save showing how they better use cover etc to advance.

    2. I suppose so - Ive always seen a save being about armour & cover etc once a shot is taken, as opposed to being able to take the shot. I suppose that works from a streamlining perspective as long as its explained - though it might be strange to have a range of different save modifiers relating to totally different things

    3. Like Bolt Action, it's just rebadged 40K.

      Basically everyone hits on a 4+ (or is it 3+ - I can't remember)... then they roll for a "save" (similar to armour saves etc, but this is a "experience save" for good use of cover etc); better units might save on 3+ and rookies 5+.

    4. Ive never seen it done this way, but potentially you could use an opposed die roll mechanism to incorporate spotting-accuracy-pentration in a single 'roll off'. I liked the way SG and TW did this with die types. Whatever the mechanism, both players need to be involved - nothing worse than watching you opponent roll a bunch of 6s and wipe you out while you watch on passively

  3. With regard to your comments on the incidence of ambushes in the Napoleonic Wars, I'm sure you're aware of the guerrilla warfare in Spain, where this would be a major feature, not dissimilar to the example of the French & Indian Wars, in spite of the difference in terrain.

    Even in set piece battles, however, the smoke which covered the battlefield made recognition of units very difficult, and the sudden appearance of bodies of troops on a flank could lead to panic. This is an excellent example of where mechanics such as blinds are called for, though cunning and even underhand behaviour by an umpire is better still. Friendly fire and even melees between friendly troops are all possible consequences of the resulting confusion.

    1. Actually, I almost added "in the Penninsular" but as my knowledge is limited to the Sharpe box set (whereas I've read many French Indian War books)....

  4. You are arguing about "information flow" in wargames. What things can I know about my enemy (and vice versa)? Can I know the composition of his army, the position his units take in the battleground, the cards he has available in its hand? There's a lot of "secrecy management" you can design.

    The best media to implement spotting/hiding mechanics is in computer games. In miniature wargames, we have to conform with all the systems you described in the article. It's a hard design trade-off, indeed. Maybe you can add little details to improve the experience, using decoy markers, for example (Surprise, it's just the wind! XD).