I suggested it in Trafalgar once..it got snowed under, and eventually the Trafalgar map faltered.
Now, you want a ship/tank/force to MOVE on the map instead of going ship/tank/force hopping over a static set map.
There IS a way to do it:
Have a map with a fixed set starting positions of the ships (beginning of battle). From ALL these ships emanate sail paths criss-cross the map.
Each ship should CHOOSE a path (as in choose a sailing direction). on these lines are dotted neutrals that you have to conquer in order to PROGRESS.
Meanwhile your conquered dots BEHIND you suffer from an ATTRITION so that you HAVE to MOVE (in practice ALL dots suffer from an attrition towards neutral..some FASTER than OTHERS..play with that concept).
At CERTAIN dots you are allowed to BOMBARD a certain set of OTHER dots of the OTHER ships' lines (in ship map: more or less perpendicular to your dot tangent).
Sometimes two ship lines MERGE sothat there WILL be a confrontation between two players.
Opposition is killed thus by bombardment, merge kills (like entering), standard attrition (boat leaks) and in fact bad dices.
*--0-0____/--0---0¦
#--0-¦----0_______\-0----0--¦
____0--0----0----0------0-----O----0----0
____ = space (or else this picture gets screwed..).
* = ship 1, # = ship 2 0 = dot /location. maybe bombardment, maybe not O = merge (entering).
(above "sketch" looks bad --discrepancy between typing page and printing page..
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)
This concept makes any new naval battle game a fresh one.
Still some history can be implemented by choosing the paths such that a certain ship can enter more than the other, can bombard more often than the other, can bombard further away lines than the other, some have tougher attrition rate than the other.
Lots to play with.
Bonus is not based on keeping a set of dots, but in keeping a certain (merge?) dot ..or keeping a certain amount of dots on a string... or keeping at least a number of dots on x number of different ship lines...
Lots of freedom to tweak.
succes
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add:
I tried to do a handsketch and already it looks like a mess if
every ship gets their own set of sail-lines.
solution: work with a whole flotilla. The bundle of "troops" spread out over a few dots on a particular line is not one ship but represents your "flotilla strength".
Do make sure the saillines have some sort of loop so that "flotillas" can sail "endlessly" if have to (unless it ends on a sandbank
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)
As you want max. 8 players you'll have to think about 8 separate flotillas (4 danes, 4 british).
add2.
Instead of set saillines you could work with open hexagons (with auto attrition on each haxgon!). Attacking another coloured hexagon would be something like entering the other flotilla.
If a partner player is blocking some hexagons..you simply don't attack..or (some cases in multplayer it pays off..to collect partner's cards!) you do.
To model the wind in one direction ; you can move /attack further hexagons always in the same direction (that is not difficult to XML).
The trouble is a fixed Bombardment direction perpendicular to your flotilla movement for each hexagon;
solution: as a flotilla you can always turn some or all of your ships in or against the wind to point your bombardment guns in any hexagon direction...
Yes, I think that is the way to do it.
See
http://www.youplay.it/play/cp_GamesPeoplePlay.asp for inspiration. (nothing visible when not logged on :s )
or rules:
http://www.youplay.it/play/ws_GameRulesSimple.asp 
Barbarus hic ego sum, quia non intellegor ulli.