DP F1997M: Arpiesse Diplomacy

About this picture	Arpiesse Diplomacy Simon Szykman

Introduction

The idea for this variant is based on a simple but significant deviation from the standard adjudication rules. In standard Diplomacy, attacks are transitive. In other words, if one attack can defeat a second, and the second attack can defeat a third, then the first attack defeats the third. In logical terms, this can be expressed something like:

a > b, b > c --> a > c (where "-->" means "implies")

In Arpiesse Diplomacy, attacks are not transitive, so that it is possible to have a set of attacks where a > b, b > c, and c > a. Such a set of attacks would not be consistent with the standard rules, but they can occur in Arpiesse Diplomacy.

In order to make adjudication possible, each unit in Arpiesse Diplomacy is assigned a color -- either red, purple or silver. The bulk of the rules of Arpiesse Diplomacy dictate the way attacks are adjudicated based on the color of the units involved. There are actually few rules, but they can result in all sorts of interesting cases, so a number of examples will be given. These rules cover as many cases as I could think up. It is possible that there is some case that I missed, so if you note any instances that are not covered by the rules, or any rules that contradict one another, please let me know.

Some people might find it odd to use colors since game pieces already have colors. This shouldn't really matter, since I don't expect that anyone playing this variant would go and add colors to game pieces. More likely, the "colors" for each of the units would be recorded on paper. The alternative would have been to use some label other than colors, but that would still require some way of recording the label for each unit. I find that picturing units with a certain color makes it easier to play out a combination of orders in my head, while picturing a "rug" army attacking a "phone" army that is supported by a "ski" fleet is pretty meaningless. If you find some alternative set of three labels preferable, feel free to substitute them for the colors. The rules will work just as well.

These simple modifications to the rules make for new (hopefully interesting) dynamics. By changing the way attacks are adjudicated, they affect strategy quite a bit. The tactical game can be quite different as well. Succesful set up of attacks and use of the support order will differ considerably from the standard game, and the traditional way of setting up stalemate lines won't work. Playing out various situations, even mentally, will bring out some of these differences.

Rules for Arpiesse Diplomacy

I. Initial Game Setup

The initial unit types and locations are the same as in standard Diplomacy. All initial units are red. Units that are built in Winter phases during the game can be of any color. If a player forgets to specify a color for a build, the defaul color is red.

II. Superiority of Colors

In order to create the non-transitivity of attacks, each color is given superiority over one of the other colors as follows:

Color	Is Superior To	Is Inferior To
Red	Silver	Purple
Purple	Red	Silver
Silver	Purple	Red

Two units of the same color are said to be equivalent to one another.

Or, put another way:

R < P, P < S, S < R, R = R, S = S, P = P

(If you can figure out where the name for Arpiesse Diplomacy came from, it will be easy to remember the order of precedence without referring to the rules. If you can't and want to know, drop me an e-mail and ask.)

III. Equivalent Attacks

Attacks among equivalent units are adjudicated exactly the same way as in standard Diplomacy. When units of like color are involved, the strength of an attack, including support(s) for the attacker and defender, determines whether or not the attack is successful.

Example 1:

Italy: Red A Ven -> Tri Red F Adr S Red A Ven -> Tri
Austria: Red A Tri HOLDS
Result: This is an equivalent attack, so the attack of strength 2 defeats the defense of strength 1. The Italian move to Tri succeeds and the Austrian unit in Tri is dislodged.

IV. Support Among Equivalent Units

Italy:	`Red A Ven -> Tri Red F Adr S Red A Ven -> Tri`
Austria:	`Red A Tri HOLDS`
Result:	This is an equivalent attack, so the attack of strength 2 defeats the defense of strength 1. The Italian move to Tri succeeds and the Austrian unit in Tri is dislodged.

Support orders for equivalent units are adjudicated exactly the same way as in standard Diplomacy.

V. Non-Equivalent Attacks

(Note that in all the examples for this section of the rules, while the attacks are made by one unit against a non-equivalent unit, the supports given to the attacker and defender all come from equivalent units; that is, in these examples, all units that receive support are supported by units of the same color. This is because there is an additional set of rules [in section VI] that govern support of units by non-equivalent units.)

For attacks among non-equivalent units:

An attack by a unit that is superior to any and all other units that are either attacking or defending the attacked location always succeeds, regardless of the strength of the attack.

Example 2:

Germany: Red A Pru -> War
Russia: Silver A War HOLDS Silver A Mos S A War
Austria: Silver A Boh -> War Silver A Gal S A Boh -> War Silver A Ukr S A Boh -> War
Result: The German attack on War is a superior attack and succeeds regardless of strength. In other words, the attack succeeds even though Russia is defending with strength 2 while Germany is only attacking with strength 1. Similarly, the Austrian attack fails, regardless of strength, because the German attack is a superior attack. Had the German unit not been involved, this would be an equivalent attack and Austria would succeed as per the standard rules.

Conversely, a defense of a location that is made by a unit superior to all units that are attacking the location always succeeds, regardless of the strength of the defense.
Example 3:

England: Purple F Nth HOLDS
France: Red F Bel -> Nth Red F Eng S F Bel -> Nth
Result: The English fleet remains in Nth because the inferior attack fails regardless of strength.

Germany:	`Red A Pru -> War`
Russia:	`Silver A War HOLDS Silver A Mos S A War`
Austria:	`Silver A Boh -> War Silver A Gal S A Boh -> War Silver A Ukr S A Boh -> War`
Result:	The German attack on War is a superior attack and succeeds regardless of strength. In other words, the attack succeeds even though Russia is defending with strength 2 while Germany is only attacking with strength 1. Similarly, the Austrian attack fails, regardless of strength, because the German attack is a superior attack. Had the German unit not been involved, this would be an equivalent attack and Austria would succeed as per the standard rules.

England:	`Purple F Nth HOLDS`
France:	`Red F Bel -> Nth Red F Eng S F Bel -> Nth`
Result:	The English fleet remains in Nth because the inferior attack fails regardless of strength.

Superiority/inferiority of attacks/defenses is adjudicated before units are dislodged; once an attack has failed, it cannot then succeed. If you think about it, this rule follows from the simultaneity of adjudication in the standard rules. [The rule is made explicit in order to address the situation in the example below.]

Example 4:

Austria: Purple A Rum HOLDS
Russia: Silver A Sev -> Rum
Turkey: Red F Bla -> Rum
Result: The Russian move to Rum succeeds because it is a superior attack. The Turkish move to Rum fails because it is an inferior attack and once failed it cannot later succeed. Therefore it is incorrect to reason that the Austrian unit is dislodged due to the Russian move, and given the Russian and Turkish moves to Rum the Turkish move should succeed because the Red Turkish fleet is superior to the Silver Russian Army.

The no-self-dislodgement rule applies, even if the attack on one's own unit is a superior attack. Neither may a support for an attack cause (that is, be necessary to cause) the dislodgement of a unit owned by the same power as the supporting unit.
Example 5:

Turkey: Red A Bul HOLDS Purple A Con -> Bul
Result: Although the attack on Bul is a superior attack, it fails because an attack may not dislodge a unit belonging the same power.

Austria:	`Purple A Rum HOLDS`
Russia:	`Silver A Sev -> Rum`
Turkey:	`Red F Bla -> Rum`
Result:	The Russian move to Rum succeeds because it is a superior attack. The Turkish move to Rum fails because it is an inferior attack and once failed it cannot later succeed. Therefore it is incorrect to reason that the Austrian unit is dislodged due to the Russian move, and given the Russian and Turkish moves to Rum the Turkish move should succeed because the Red Turkish fleet is superior to the Silver Russian Army.

Turkey:	`Red A Bul HOLDS Purple A Con -> Bul`
Result:	Although the attack on Bul is a superior attack, it fails because an attack may not dislodge a unit belonging the same power.

If there are two or more equivalent attacks of equal strength into an occupied location, the beleaguered garrison rule applies even if the attacking units are superior to the one that occupies the space. This, too, is a logical extension of the standard rules, but it is made explicit for completeness.

Example 6:

England: Silver A Bel HOLDS
France: Red A Bur -> Bel Red A Pic S A Bur -> Bel
Germany: Red A Ruh -> Bel Red A Hol S A Ruh -> Bel
Result: Despite the fact that the French and German units are superior to the English unit, due to the beleaguered garrison rule the English unit is not dislodged because the attacks into Bel are of equal strength and bounce.

England:	`Silver A Bel HOLDS`
France:	`Red A Bur -> Bel Red A Pic S A Bur -> Bel`
Germany:	`Red A Ruh -> Bel Red A Hol S A Ruh -> Bel`
Result:	Despite the fact that the French and German units are superior to the English unit, due to the beleaguered garrison rule the English unit is not dislodged because the attacks into Bel are of equal strength and bounce.

If a combination of attacks cannot be resolved logically due to a paradox or "looping", then all attacks fail.

Example 7:

Italy: Purple A Ven -> Tri
Turkey: Red A Ser -> Tri Red A Alb S Red A Ser -> Tri
Austria: Silver A Tyr -> Tri Silver A Bud S A Tyr -> Tri Silver A Bud S A Tyr -> Tri
Result: The Italian attack is superior to the Turkish attack, the Turkish attack is superior to the Austrian attack, and the Austrian attack is superior to the Italian attack (the superiority of an attack is unaffected by supports and associated attack strengths). These attacks cannot be resolved so all attacks fail. Love that non-transitivity.

VI. Support Among Non-Equivalent Units

Italy:	`Purple A Ven -> Tri`
Turkey:	`Red A Ser -> Tri Red A Alb S Red A Ser -> Tri`
Austria:	`Silver A Tyr -> Tri Silver A Bud S A Tyr -> Tri Silver A Bud S A Tyr -> Tri`
Result:	The Italian attack is superior to the Turkish attack, the Turkish attack is superior to the Austrian attack, and the Austrian attack is superior to the Italian attack (the superiority of an attack is unaffected by supports and associated attack strengths). These attacks cannot be resolved so all attacks fail. Love that non-transitivity.

As in standard Diplomacy, a unit receiving support moves or defends with its own strength plus that of all (uncut) supporting units. In Arpiesse Diplomacy, if a unit receives support from a superior unit, it moves or defends with the superior color as well as its own color.

Example 8:

Russia: Red A Sil HOLDS Purple A War S A Sil Silver A Pru S A Sil
Result: Because the unit in Sil is receiving support from a superior unit in War, it defends as a Red and Purple unit. It does not receive the color Silver from the army in Pru because that unit is not a superior unit.

Russia:	`Red A Sil HOLDS Purple A War S A Sil Silver A Pru S A Sil`
Result:	Because the unit in Sil is receiving support from a superior unit in War, it defends as a Red and Purple unit. It does not receive the color Silver from the army in Pru because that unit is not a superior unit.

A unit may not obtain an inferior color through support, even if the support comes from a superior unit.

Example 9:

England: Purple F Lon S F Nth Red F Nth S F Eng Silver F Eng HOLDS
Result: The unit in Nth is receiving support from a superior unit, and therefore defends with that unit's color as well as its own (i.e., Red and Purple). The Silver unit in Eng is also receiving support from a superior unit. However, it cannot receive the color Purple to defend with, even though it is receiving support from a superior unit, because Purple is an inferior color for the Silver unit. Eng can only receive the superior color, Red in this case, and therefore the fleet in Eng defends as Silver and Red, but not Purple.

Just as a unit that offers support in standard Diplomacy does not give up its own defensive strength to order the support, in Arpiesse Diplomacy a unit that supports another unit does not give up its color by doing so.
In standard Diplomacy, if a unit receives support for an attack and that attack fails, the unit defends its own location against attack with its own strength but not the strength of any support it had received for its failed attack. Similarly, in Arpiesse Diplomacy, if a unit receives support for an attack and that attack fails, it defends its original location against attack with only its own strength and color. Any colors obtained through support for the attack are not available for defensive purposes.

VII. Cutting Support

England:	`Purple F Lon S F Nth Red F Nth S F Eng Silver F Eng HOLDS`
Result:	The unit in Nth is receiving support from a superior unit, and therefore defends with that unit's color as well as its own (i.e., Red and Purple). The Silver unit in Eng is also receiving support from a superior unit. However, it cannot receive the color Purple to defend with, even though it is receiving support from a superior unit, because Purple is an inferior color for the Silver unit. Eng can only receive the superior color, Red in this case, and therefore the fleet in Eng defends as Silver and Red, but not Purple.

The cutting of support is handled as in standard Diplomacy with the exception that an inferior unit cannot cut support ordered by a superior unit. The cutting of support affects (that is, nullifies) both the increase in attack/defense strength and the passing of a color from a superior unit (if applicable) as described in Rule VI.

VIII. Resolving Multi-Color Attacks and Defenses

A unit attacking or defending with multiple colors can be thought of as making multiple attacks or defenses, each with one color, and each having the full strength of itself and its (uncut) supports (that is, its strength is not divided up among these theoretically separate attacks, each by a different color).
To dislodge a unit that is holding with multiple colors, an attacking unit must make an attack that defeats each and every one of the holding unit's defenses.
This is not the same as saying that a defending unit must be able to defend against each of the attacking unit's attacks (which would make it easier for an attack to succeed). The burden to succeed is on the attacker, not the defender.
This is also not the same as saying that a defending unit must be able to defend against any one of the attacking unit's attacks (which would make it harder for an attack to succeed).

IX. Resolving Multi-Color Attacks by Multiple Units

When two or more units attempt to enter an empty province attacking with multiple colors, each unit can, as before, be thought to be making multiple attacks each with one color.

If each of a unit's attacks can defeat each of the other attacking units' attacks, the first unit succeeds in entering the empty space.
Also, if each of a unit's attacks can beat or tie each of the other attacking units' attacks, the first unit still succeeds in entering the empty space. (Note that at least one of the unit's attacks must beat, rather than tie, those of the other units, since if they all tie, a standoff results.)
If the above rules cannot be logically or consistently resolved (for example, if more than one unit satisfies the above rules and successfully attacks the same space) or if a paradox of any sort results, all attacks fail and a standoff results.

When two or more units attempt to enter an occupied province, attacking with multiple colors, but the unit occupying the provice successfully moves out of that province, the province should be considered empty and the above rules apply. If the unit occupying the provice is holding, or fails to leave the province, the province is considered to be occupied and the following rules apply:

To enter the space, a unit must first be able to successfully attack that space as if it were an empty space, according to the rules given above.
That unit must also be able to successfully dislodge the defending unit according to the rules in Section IX. Note that this order is important: first, a single unit must be able to move in as if the space were empty and then it must be able to dislodge the unit occupying the province. This is not the same as saying that units must be able to dislodge a defending unit and then any units that can do so must be able to attack as if the space were empty. In some cases, an attack that would succeed one way would fail the other, so be sure to consider the correct ordering.
Once again, If the above rules cannot be logically or consistently resolved or if a paradox of any sort results, all attacks fail and a standoff results.

X. The Retreat Order

Retreats are handled as in standard Diplomacy, with the exception that if two or more units are ordered to retreat to the same space, then if one unit is superior to the other(s), the retreat for the superior unit succeeds and only the inferior unit or units are disbanded.

XI. The Convoy Order

Convoys are handled as in standard Diplomacy. A fleet need not be a certain color in order to convoy any particular army.

XII. Optional "Color Exchange" Rule

A Summer phase is added between the Spring and Fall phases. During the Summer phase, each unit may submit an exchange order, of the form:

"Unit-1 exchange with Unit-2" (any non-ambiguous syntax is acceptable, such as omitting the word "with" or using "Exch" or "X" rather than "exchange").

If and only if two units submit the same exchange order for one another, and if the two units are located such that either one could support the other's HOLD order (even if both can't support each other's HOLD orders) then the two units switch colors. Note that it is not necessary for either unit to actually support a HOLD order before or after the exchange -- it must merely be possible for one to do so.

Example 10:

Italy: Purple F Adr X A Tri
Austria: Silver A Tri X F Adr
Result: The units in Tri and Adr both have submitted an order for the same exchange. Since the fleet in Adr is located such that it could support Tri to HOLD, the units exchange colors even though the army in Tri cannot support the fleet which is located in a body of water.

Example 11:

Russia: Red F StP(SC) X F Nwy
England: Purple F Nwy X F StP(SC)
Result: Although the fleet in StP(SC) cannot support the fleet in Nwy to HOLD, the fleet in Nwy can support the fleet in StP(SC) to hold, so the units exchange colors.

Example 12:

France: Red F Gas X F Mar Silver F Mar X F Gas
Result: Although the Mar and Gas fleets are adjacent to one another, neither fleet can support the other to HOLD so the exchange order is not valid. If either unit had been an army, the exchange would succeed.

Italy:	`Purple F Adr X A Tri`
Austria:	`Silver A Tri X F Adr`
Result:	The units in Tri and Adr both have submitted an order for the same exchange. Since the fleet in Adr is located such that it could support Tri to HOLD, the units exchange colors even though the army in Tri cannot support the fleet which is located in a body of water.

Russia:	`Red F StP(SC) X F Nwy`
	`England: Purple F Nwy X F StP(SC)`
Result:	Although the fleet in StP(SC) cannot support the fleet in Nwy to HOLD, the fleet in Nwy can support the fleet in StP(SC) to hold, so the units exchange colors.

France:	`Red F Gas X F Mar Silver F Mar X F Gas`
Result:	Although the Mar and Gas fleets are adjacent to one another, neither fleet can support the other to `HOLD` so the exchange order is not valid. If either unit had been an army, the exchange would succeed.

[Note: In the rules above, I haven't provided quite as many examples as I wanted to, particularly in sections VIII and IX. I'll plan on adding some more examples next week. If you have any opinions or feedback (good or bad) I'd be interested in hearing from you. And if you are interested in trying a game of Arpiesse Diplomacy, let me know. If I get seven players, I'll start a game, though I suspect the adjudication will be quite a challenge.]

Simon Szykman
(simon@diplom.org)

If you wish to e-mail feedback on this article to the author, click on the letter or envelope above. If that does not work, feel free to use the "Dear DP..." mail interface.

About this picture

Arpiesse Diplomacy

Simon Szykman

Introduction

Rules for Arpiesse Diplomacy