Scirocco

Of the making of these games there need be no end, and I have no doubt that many other varieties have been proposed and perhaps played, of which we have been spared the knowledge....

—H.J.R. Murray, A History of Chess

Play Scirocco against the computer through Jocly

Scirocco is a chess variant played on a 10 by 10 board. It was invented in 1998 and 1999 by Adrian King (your humble author), and revised in 2001, and again in 2009. The original Scirocco was a submission for the the contest to design large chess variants.

The Revision

I revised the ZRF for Scirocco in 2001 at the urging of Kerry Handscomb, editor of Abstract Games magazine, who wanted a game that better lent itself to the construction of a physical set for over-the-board play. The complex promotion rules for some of the pieces in the original game required the addition of several pieces that would start off-board, along with some kind of reminder to use the quirky rules when promoting the affected pieces. Since that revision, every piece promotes just one way and follows the same promotion rule. Each player starts out with two additional pieces, an Alfil and a Dabbaba. After some playtesting, I think the new starting position results in a smoother game, entirely aside from the simpler promotion rules.

Unfortunately, laziness and other distractions prevented me from posting the 2001 revision until late 2008.

In late 2008 and early 2009, inspired by some comments by John Smith, I did some experiments with the Dervish and Harpy, and adjusted their moves to make each of them a little stronger. The Dervish now relays a limited Firzan move, as well as its original Alfil and Dabbaba moves, to adjacent pieces (the limitation is that the relayee must end its move adjacent to the Dervish). The Harpy, which was difficult to position so that many pieces could take advantage of its Knight relay, now relays as a Q3 instead of a Knight. Lest this change make it too strong, it also moves as a Q3 instead of a Queen, as it did originally.

The 2009 revision also loosens up the initial array, allowing players to swap each pair of pieces across the vertical midline of the board, as long as the overall array has either rotational or mirror symmetry. This is the same rule as in Scirocco's larger cousin Typhoon. The ZRF still contains the older fixed arrays as an option.

I still describe the older rules here for those who are interested, but they appear in italics in a smaller font.

Principles I Tried to Follow in Designing Scirocco

I designed Scirocco to satisfy my own taste in chess variants. Some of the principles that I like are:

• Too many powerful pieces on the board, at least at the start of the game, make the game too fast and tactical.
• A wider variety of pieces makes the game more interesting, because a wider of variety of situations can develop.
• If pieces have a finely graded range of values, figuring out what to exchange for what is an interesting problem.
• An 8 by 8 board is small.
• Making stalemate a win for the player who gives it reduces the number of draws. That is good, because draws are boring.
• If (almost) every piece promotes instead of just Pawns, the game will probably be less drawish, because of the increased power on the board in the endgame. Also, the ending will be more tactical, with more potential for surprising endings.
• If promoting a piece is optional, and the promoted piece's abilities are not a strict superset of its unpromoted abilities, then sometimes it may be better not to promote a piece when you can. This kind of choice adds interest to the game.

• Every piece except the Pawn has a move that is the same forwards and backwards, and left and right. (In some variants, like Shogi, pieces have asymmetric moves).
• Each player has only one of each kind of piece, except for the Pawns, Guards, and the eponymous Scirocco.
• The initial density of pieces on the board is 54%, not much more than the 50% of Orthochess.

The Inspiration for Scirocco

The Courier (believed then to be the strongest piece) moved as the modern B...

When I saw this I thought, What if the Courier were indeed the strongest piece in Courier Chess? You could change the move of the Courier to make it stronger, and perhaps reduce the strength of the true strongest piece in Courier Chess, the Rook.... Pursuing these ideas farther, the Courier evolved in my mind into the Scirocco, the shape of the 12 by 8 Courier Chess board changed to the 10 by 10 Scirocco board, and I added various pieces that I hope will make an interesting game.

To me, Scirocco has a sort of “antique” feel, like the chess variants from the medieval Islamic world. I named the game (and the most important piece in the game) for the wind that blows from the Sahara into Europe because that wind seemed like a good emblem for the Arabic influence that brought to Europe the game of Shatranj, which evolved into the modern Orthochess.

A Gentle Plea for Unnecessary Complexity

An elegant game combines minimum rules with maximum strategy.... Many inventors assume that making a game more complicated will make it better but usually the opposite is true.

• Although the number of types of piece in the game is large (36), it is not so difficult to learn the moves of the pieces as you might suppose. There is a fair amount of symmetry in the initial array, and there are some obvious patterns in the ways in which pieces promote. Furthermore, I use (and encourage the use of) flat, Shogi-type pieces displaying small diagrams showing how each Scirocco piece moves, so that it is hard to make a mistake.

• In a sense, I have followed Pritchard's dictum, in that the concept I wanted to realize in Scirocco was the interaction of a large number of different kinds of pieces. I think I have done this with a minimum of distracting extra rules; the complexity inheres in the moves of the pieces, and not in exceptions to more general rules (like the castling move or 2-step initial Pawn move in Orthochess).

• Finally, if a game is playable, who cares if it's minimal? This is, after all, an entry into a contest for large chess variants; if you want something small, play one of the various species of 5 x 5 games called Minichess. If you want something austerely elegant, play Christian Freeling's Chad. Or better yet, play Go.

  I don't think it's a big drawback for a large chess variant to require a few minutes of study before you learn the moves. Great Chess is one of the Great Mysteries of the human mind, and there's nothing wrong with having to go through a bit of an initiation. I say, revel in the pointless intricacies of the universe.

Setup

Each player's first three ranks look, in words, something like this:

• For Blue:
  Ch a1; A b1; St c1; N e1; C f1; De g1; Go h1; D i1; Wa j1;
  Pr b2; Sc c2; K d2; W e2; F f2; Co g2; Sc h2; Ma i2;
  P a3, b3; Gu c3; P d3-g3; Gu h3; P i3, j3
• For Tan:
  Ch j10; A i10; St h10; N f10; C e10; De d10; Go c10; D b10; Wa a10;
  Pr i9; Sc h9; K g9; W f9; F e9; Co d9; Sc c9; Ma b9;
  P j8, i8; Gu h8; P g8-d8; Gu c8; P b8, a8

or like this:

• For Blue:
  Wa a1; D b1; Go c1; De d1; C e1; N f1; St h1; A i1; Ch j1;
  Ma b2; Sc c2; Co d2; F e2; W f2; K g2; Sc h2; Pr i2;
  P a3, b3; Gu c3; P d3-g3; Gu h3; P i3, j3
• For Tan:
  Wa j10; D i10; Go h10; De g10; C f10; N e10; St c10; A b10; Ch a10;
  Ma i9; Sc h9; Co g9; F f9; W e9; K d9; Sc c9; Pr b9;
  P j8, i8; Gu h8; P g8-d8; Gu c8; P b8, a8

In fact, you can use a variety of initial arrays. Blue first places the Kings and Commoners, thereby determining whether the overall setup has mirror symmetry or rotational symmetry. Tan then chooses how to place each pair of pieces, where a pair are two pieces shown in the above diagram on the same rank but on files an equal distance from the vertical centerline of the board. For example, the Chariot and Wagon constitute a pair; for Blue, one on a1 and one on j1, and for Tan, one on a10 and one on j10. Tan can place either the Blue Chariot or the Blue Wagon on a1, but (because the placement of the Kings and Commoners has already determined the overall symmetry of the setup) placing one Chariot or Wagon fixes the placement of the others.

The complete list of exchangeable pairs is Chariot-Wagon; Alfil-Dabbaba; Goat-Stork; Camel-Knight; Firzan-Wazir; King-Commoner; Marquis-Priest; and the Dervish, which is paired with an empty space.

For example, if Blue places both Kings on the g file, the setup has mirror symmetry, and two pieces of the same type must go on the same file. If Tan puts the Blue Chariot on a1, then (by mirror symmetry) the Tan Chariot must go on a10, and the two Wagons on j1 and j10. Similarly, if Tan puts the Blue Alfil on b1, then the Tan Alfil goes on b10, and the Dabbabas on i1 and i10, and so on.

Here is an example of a mirror-symmetric setup, as opposed to the rotationally symmetric setup at the top of the page:

Because there are eight pairs of pieces whose positions can be exchanged (exchanging the two Scirocchi has no effect), there are 256 different initial starting arrays, although half of them are effectively identical to their mirror images, because all Scirocco pieces have moves with right-left symmetry.

In previous revisions, only the setup shown above or a mirror image of it were permitted. Tan chose the setup used by each player. Thus, there were 4 possible initial configurations altogether, which were known by the piece starting out in each player's lower-left corner:

• Chariot-Chariot Setup: Blue Chariot a1, Tan Chariot j10.
• Chariot-Wagon Setup: Blue Chariot a1, Tan Wagon j10.
• Wagon-Chariot Setup: Blue Wagon a1, Tan Chariot j10.
• Wagon-Wagon Setup: Blue Wagon a1, Tan Wagon j10.

The setup for the original 1999 version was the same, except that the Alfil and Dabbaba were absent; they appeared only as the result of promotions.

Pieces

Note that none of the initial pieces is as powerful as a Rook. I wanted to get away from the every-piece-an- Amazon feel of many modern chess variants, and encourage a more contemplative and less tactical opening than such games lead to. Ralph Betza's DemiChess is another recent variant with a similar aim (by someone who is a far better chess player than I am).

The Pawn, Guard, and Scirocco all have special promotion rules, as explained below.

In alphabetical order:

Abbot (Ab)

• Promoted Marquis

The Abbot moves and captures like a Knight, or like a Bishop, but not farther away than 4 spaces.

The Abbot is based on the frequently invented combination of Knight and Bishop. Since Grand Chess was a part of the inspiration for this game, I thought I should have a Knight + Bishop piece in the game somewhere, but I seemed to have too many strong promoted pieces, so I limited the range of the Bishop movement. The Knight + Bishop combination is called the “Cardinal” in Grand Chess, and I thought I'd keep the ecclesiastical theme in the Abbot's name (as well as the Priest's).

Alfil (A)

• Promotes to Bishop

The Alfil is a (2,2) leaper; that is, it leaps 2 spaces diagonally, ignoring any intervening piece.

The Alfil is a piece of ancient lineage, being the predecessor to the modern Bishop, to which it promotes in this game.

In the old revision, the Pawn promoted to an Alfil, and then the Alfil to a Dabbaba.

Bishop (B)

• Promoted Alfil

The Bishop moves the same as its Orthochess equivalent; that is, it moves when not capturing diagonally any number of clear spaces, and captures by moving diagonally across any number of clear spaces to the first space occupied by an opposing piece, which the Bishop replaces.

In this revision, the Bishop is a promoted Alfil, but in the old revision, the Bishop was a promoted Zebra, and was also able (as an exception to the usual promotion rules) to promote back to a Zebra.

Camel (C)

• Promotes to Squirrel

The Camel is a (3,1) leaper; that is to say, it leaps directly to any space that could be reached by moving 3 spaces along any rank or file, and then one space at right angles. It is thus a sort of extended, colorbound Knight.

The Camel is exactly the sort of piece I wanted to showcase in Scirocco: fairly weak, but not worthless (it's worth a little less than a Knight). The Camel's movement geometry is also different from that of every other unpromoted piece, so that it can attack without being attacked.

Chariot (Ch)

• Promotes to Octopus

The Chariot moves and captures like a Rook, but not farther away than 4 spaces.

The Chariot is one of the 2 Rook-like pieces I derived by reducing the strength of a Rook, so that the Scirocco could claim to be the most powerful piece on the board (at least initially).

Ralph Betza has conducted some experiments with this piece.

Commoner (Co)

• Promotes to Wildebeest

The Commoner (known in some games as the “Mann”) moves and captures exactly like a King, but is not royal (capturing it does not end the game).

This piece is retained from Courier Chess, although I moved it away from the King in the initial layout to make the layout more symmetric.

Dabbaba (D)

• Promotes to Genie

The Dabbaba is a (2,0) leaper; that is, it leaps 2 spaces orthogonally, ignoring any intervening piece.

The name “Dabbaba” was used for various unorthodox pieces in medieval Islamic chess variants. The move we generally associate with this name today is the one from Timur's Great Chess. The word “dabbaba” means a kind of war machine; its English translation is “sow”, but I have no idea what it looks like.

To discourage you from trading away this weak piece too quickly, in the new revision, I made it promote to the powerful Genie. Strategy in this game often consists of figuring out a way to escort the Dabbaba to the promotion zone.

In the old revision of this game, the Dabbaba was a part of the complex promotion sequence of the Pawn.

Dervish (De)

• Promotes to Harpy

The Dervish moves and captures 2 steps orthogonally or diagonally. It leaps any intervening piece without capturing or being blocked by it. In addition, any friendly piece on any of the 8 adjacent squares may move or capture as a Firzan, Dabbaba, or Alfil, but only to a destination that is also adjacent to the Dervish. That is, a friendly piece can leap to the opposite side of the Dervish, or an orthogonally adjacent friendly piece can move one step diagonally around the Dervish, clockwise or counterclockwise. Thus, if you have a Dervish on g5 and Pawns on f4 and h5, the Pawn on f4 may leap to h6 (or make a normal Pawn move), and the Pawn on h5 can move to g6 or g4 (or make a normal Pawn move to h6, if empty).

A piece cannot promote on a turn when it uses the Firzan-, Dabbaba-, or Alfil-like move relayed by a Dervish; it can promote only when moving under its own power.

A dervish is a Muslim ascetic. Dervish orders are known for their whirling dances (to induce a trance-like state). The movements of the adjacent pieces around and across the Dervish reminded me of whirling, whence the name.

Before the 2009 revision, the Dervish did not relay the Firzan move, only the Dabbaba and Alfil moves.

Duke (Du)

• Promoted Priest

The Duke moves and captures like a Knight, or like a Rook, but not farther away than 4 spaces.

The Duke is to the Marquis as the Abbot is to the Priest; it extends the one-step move to a 4-step ride. However, I made the Marquis promote to the Abbot, not to the Duke, so that the promoted Marquis wouldn't be a superset of the Marquis (meaning there might be situations where you would decline promotion). Hence the Priest promotes to the Duke, not to the Abbot.

The Knight + Rook combination is called the “Marshall” in Grand Chess, and I thought I'd give this piece a vaguely military sounding name. “General” sounded too much like “Genie”, and is also the translation of “Firzan”. The two-character abbreviation for “Colonel” would have been identical to that of “Commoner”. I settled on “Duke”; the name is hard to confuse with that of other pieces, and was originally a military title, from Latin dux, meaning “leader”.

Emperor (Em)

• Promoted King

The Emperor moves and captures one or 2 steps orthogonally, or 2 steps diagonally. When moving 2 steps, it leaps any intervening piece without capturing or being blocked by it. In other words, the Emperor moves as a Wazir, Dabbaba, or Alfil.

The Emperor is more difficult to catch than a King, especially if it is in the middle of the board. However, it is vulnerable to attacks from diagonally adjacent squares, so it is not always wise to promote a King to an Emperor.

Firzan (F)

• Promotes to Zig

The Firzan, also known variously as “Fers”, “Ferz”, or “Farzin”, moves and captures one step diagonally.

The Firzan (Arabic, from the Persian word for “general”) was present in the oldest forms of chess of which we are aware, but has been replaced in Orthochess by the Queen. The Firzan is also present in Courier Chess.

Frog (Fr)

• Existed only on the old revision of this game

The Frog moved and captured as a Commoner or as a (3,0) or (3,3) leaper; that is, it could move to an adjacent square, or leap to a square 3 steps away orthogonally or diagonally (ignoring any intervening pieces).

The Frog was the end point of the old revision's promotion sequence of the Pawn. It has been discarded entirely in the new revision, because it was overly strong for a regular Pawn promotion; its replacement is the similar but weaker Tadpole.

Genie (Ge)

• Promoted Dabbaba

The Genie moves and captures as a Queen, but not farther away than 3 spaces. In addition, the Genie can capture an opposing piece on an (orthogonally or diagonally) adjacent square without moving.

The Genie is generally the most powerful piece in the game because of its ability to capture a protected piece without exposing itself to harm. However, it is not always easy for the Dabbaba to survive the journey to the promotion zone, so the Genie appears only in some games.

In the old revision, the Scirocco promoted to a Genie, but only after an orthogonal move.

Goat (Go)

• Promotes to Lioness

The Goat moves and captures by leaping 2 steps orthogonally (like a Dabbaba); it may also move one square diagonally, but not to capture. When moving 2 steps, it leaps any intervening piece without capturing or being blocked by it.

The Goat is a weakened form of Kirin, a piece from Chu Shogi. The Kirin can capture as well as move one step diagonally. I wanted to add the Kirin for a bit of Chu Shogi flavor, but I already had too many 8-fold leapers, so I toned it down a bit and gave it a less exotic name.

Guard (Gu)

• Promotes to Zebra

The Guard moves without capturing one step orthogonally, or captures one step diagonally. It is a sort of omnidirectional Pawn.

The Guard's Pawn-like nature allows it to participate in a Pawn chain, but unlike an easily blocked Pawn, it can get up and leave if it becomes bored.

In the old revision, the Guard, along with the Pawn and the Scirocco, had special rules governing its promotion. The Guard promoted to a Zebra in the usual way; however, the Zebra also promoted to a Bishop, again subject to the usual promotion rules. That Bishop, however, was entitled to promote back to a Zebra (again, only under the standard promotion conditions), which could then promote back to a Bishop, and so on. Although I'm partial to unnecessary complexity, this was unnecessarily unnecessary.

Harpy (Ha)

• Promoted Dervish

The Harpy moves like a Queen up to 3 steps, but cannot capture by itself. However, any friendly piece on open Queen-lines up to 3 steps away from the Harpy is temporarily granted the additional power to move and capture like a Knight (as long as it starts its move a 3-step Queen's move away from the Harpy); pieces that can already move like a Knight are not affected. A piece cannot promote on a turn when it uses the Knight's move relayed by a Harpy; it can promote only when moving under its own power.

The Harpy is kin to the Knight in Knight-Relay Chess, but unlike the Relay Knight, a Harpy is not immune from capture.

The Harpy's usefulness varies, depending on how many pieces you have left. It is quite powerful if you can promote it early while you still have several Pawns and other weak pieces that can benefit from the additional Knight moves.

Before the 2009 revision, the Harpy moved as a Queen, but relayed the Knight's move to pieces a Knight's move away. Because fewer pieces benefited from the Knight relay, it was a distinctly weaker piece than the current Harpy.

King (K)

• Promotes to Emperor

The King moves and captures one step to any of the 8 orthogonally and diagonally adjacent squares. Capturing the opposing King or Emperor wins the game (by convention, the game more commonly ends with checkmate, an unstoppable threat to capture the King or Emperor. However, note that the victory conditions for Scirocco are different from those of Orthochess).

The King has moved the same way for almost a millennium and a half, so why mess with success?

Knight (N)

• Promotes to Rook

The Knight is a (2,1) leaper; that is to say, it leaps directly to any space that could be reached by moving 2 spaces along any rank or file, and then one space at right angles.

The Knight is a piece retained from the earliest known forms of chess. I placed it towards the center because it seemed a little difficult to develop from the wings on the 10 by 10 board, where it starts out in Grand Chess, but it isn't particularly easy to develop from its back-rank initial position in Scirocco, either.

Lioness (Li)

• Promoted Goat

The Lioness can leap to any square a King could reach in 2 moves; that is, it is a combination of Wazir, Firzan, Dabbaba, Knight, and Alfil.

The Lioness is inspired by the Chu Shogi piece called the Lion. In addition to moving like the Lioness, the Lion can make 2 full King-type moves on a single turn, with the ability to capture pieces on both parts of the move, or to move back to the starting square. This seemed like too much power to put on the board in Scirocco, even in the endgame, so I used the weaker (but still impressive) Lioness, which is worth roughly as much as a Queen.

The promotion of Goat to Lioness also has a Chu Shogi origin; in Chu Shogi, the Kirin, which inspired the Goat, promotes to a Lion.

Marquis (Ma)

• Promotes to Abbot

The Marquis moves and captures like a Wazir or a Knight.

The antecedent of the Marquis is the Marshall (Rook + Knight) of Christian Freeling's Grand Chess, but the Marshall is much too powerful (worth nearly as much as a Queen) to be a starting piece in Scirocco.

Octopus (Oc)

• Promoted Chariot

The Octopus moves one step diagonally, then like a Rook orthogonally, but only in a direction away from its starting square. That is, it cannot reach an orthogonally adjacent square. It can both move and capture on the Rook-like part of its move, but it can only move without capturing to the diagonally adjacent square. That means that the closest square on which it can make a capture is a Knight's move away.

The name “Octopus” for this piece comes from a copy of some unpublished material on a game concept called “Generalized Chess” by the great game inventor Wayne Schmittberger, forwarded to me by Edward Jackman. It wasn't clear from Wayne's description whether his Octopus could actually move one space diagonally or had to move at least as far as a Knight, so I split the difference and allowed the Scirocco Octopus to move like a Firzan but not to capture like one.

The ultimate ancestor of the Octopus is probably the Giraffe of Timur's Great Chess. Timur's Giraffe moves differently from the piece we usually know today as the Giraffe; Timur's Giraffe moves like the Octopus, but must move a minimum distance of 4 steps, i.e., at least as far as a modern Giraffe's move.

Pawn (P)

• Promotes to Tadpole

The Pawn moves one step straight ahead when not capturing, or one step diagonally forwards (left or right) to capture. Unlike the Orthochess Pawn, the Pawn in Scirocco does not have the option of making a 2-step move.

The Pawn promotes to the Tadpole, which is powerful enough to be useful in the endgame, but not overwhelming.

In the old revision, the Pawn promoted to the Alfil, which is worth barely more than a Pawn. The Alfil in turn promoted to the Dabbaba, which is scarcely worth more than the Alfil. The Dabbaba, promoted to the Frog, which was reasonably powerful.

The reason for the Pawn's long promotion sequence was that although I wanted it to promote to a piece strong enough to make a difference in the endgame, it didn't seem fair to promote the Pawn to a piece too far out of proportion with the Pawn's own strength. So I made the Pawn first go through the ritual of promoting to Alfil and Dabbaba before it could become a Frog. Subsequent playtesting has shown that the current rules are just as entertaining but easier to understand.

Priest (Pr)

• Promotes to Duke

The Priest moves and captures like a Firzan or a Knight.

The antecedent of the Priest is the Grand Chess Cardinal (Bishop + Knight), just as that of the Marquis is the Grand Chess Marshal.

Queen (Q)

• Promoted Stork

The Queen moves and captures like a Rook or Bishop, as in Orthochess.

The promotion of the Stork to the Queen was inspired by the Chu Shogi Phoenix's promotion to Free King. In Chu Shogi, the Free King moves just like an Orthochess Queen, and the Scirocco Stork was derived from the Phoenix.

Rook (R)

• Promoted Knight

The Rook moves the same as its Orthochess equivalent; that is, it moves when not capturing orthogonally any number of clear spaces, and captures by moving orthogonally across any number of clear spaces to the first space occupied by an opposing piece, which the Rook replaces.

The Rook has moved the same way since the earliest forms of chess, but it was too powerful as an initial piece for Scirocco.

Scirocco (Sc)

• Promotes to Vulture

The Scirocco, for which the game is named, is the most powerful of the pieces initially on the board. The Scirocco moves and captures one step orthogonally or any number of steps diagonally, that is, as a Wazir or Bishop. This is the same as the move of the promoted Bishop (or Dragon Horse) in Shogi; the Dragon Horse also exists as an unpromoted piece in Chu Shogi.

The Scirocco, like the Pawns and Guards, is unusual among the pieces in this game in that each player starts off with more than one. I figured that if I wanted to model my game after Courier Chess, then as in that game, I should have a setup where there were twin stars of the show (the 2 Scirocchi) arranged symmetrically about the center.

When I first started play-testing this game, the Scirocco promoted to a Genie. However, Genies dominated too many of the endgames. Giving the Dabbaba the Genie promotion and promoting the Scirocco to the weaker Vulture seems to result in more endgame variety.

In the old revision, the Scirocco (like the Pawns and Guards) was also governed by unusual promotion rules. Like any other piece, the Scirocco could promote only at the end of a move that started or ended within the promotion zone, but in the case of the Scirocco, the promotion allowed depended on the kind of move the Scirocco made. After a diagonal move, the Scirocco promoted to a Vulture; after an orthogonal move, to a Genie.

Spider (Sp)

• Promoted Wagon

The Spider moves one step orthogonally, then like a Bishop diagonally, but only in a direction away from its starting square. It can both move and capture on the Bishop-like part of its move, but it can only move without capturing to the orthogonally adjacent square. That means that the closest square on which it can make a capture is a Knight's move away.

The Spider is the diagonal counterpart of the orthogonal Octopus, and like the Octopus, was taken from an unpublished piece by Wayne Schmittberger.

Squirrel (Sq)

• Promoted Camel

The Squirrel moves and captures as a Dabbaba, Knight, or Alfil.

The Squirrel is among the many interesting pieces that appears in Anthony Dickins's A Guide to Fairy Chess. Dickins ascribes its invention to N. Kovacs of Budapest.

Stork (St)

• Promotes to Queen

The Stork moves and captures by leaping 2 steps diagonally (like an Alfil); it may also capture one square orthogonally, but not move there without capturing. When moving 2 steps, it leaps any intervening piece without capturing or being blocked by it.

The Stork is a weakened form of Phoenix, a piece from Chu Shogi. The Phoenix can both move and capture one step orthogonally.

Tadpole (Ta)

• Promoted Pawn

The Tadpole moves and captures like a Firzan or like a (0,3) leaper. It can also capture like a Wazir. It is a toned-down version of the Frog, which was the promotion of the Pawn in the earliest versions of the game, but which wound up dominating too many endgames.

Vulture (Vu)

• Promoted Scirocco

The Vulture captures like a Rook and moves without capturing like a Bishop. It may also capture like a Firzan and move without capturing like a Wazir, so that it can both move and capture on adjacent squares.

Wagon (Wa)

• Promotes to Spider

An adjacent-space restriction similar to the Wagon's is also found in the Talia, or Scout, in Timur's Great Chess (the web page translates “Talia” as “Picket”). However, the Talia moves as a restricted Bishop, rather than a restricted Rook.

I wanted a weakened form of the Rook so that the Rooks would not steal the show from the Scirocco. Of all the spaces a Rook can move to, the immediately adjacent spaces are probably the most important (at least until the board opens up), so removing the ability to reach an adjacent space makes the Wagon weaker than the Rook by more than you might expect. I chose the name “Wagon” because its meaning is similar to “Chariot”, the original name of the Rook; wagons are generally less maneuverable than chariots, so the name seemed appropriate.

Wazir (W)

• Promotes to Zag

The Wazir moves and captures one step orthogonally.

The name “Wazir” (Arabic, “vizier”, meaning a government minister or adviser), like the name “Dabbaba”, was used for pieces with different moves in different medieval Islamic chess variants. The Wazir's move in Scirocco is the one commonly used today, and is the same as in Timur's Great Chess.

The Wazir in Scirocco has sufficiently low mobility that it is seldom worthwhile advancing it, and it often winds up as a defender of the King in the endgame.

Wildebeest (Wi)

• Promoted Commoner

The Wildebeest moves and captures like a Knight or Camel.

The Wildebeest, also called the Gnu (“gnu” being another word for “wildebeest”), is among the pieces described in Anthony Dickins's A Guide to Fairy Chess. Wayne Schmittberger liked the piece well enough to name a chess variant, Wildebeest Chess, after it.

Zag (Za)

• Promoted Wazir

The Zag moves and captures like a Firzan or Alfil; in addition, it may leap an orthogonally adjacent hostile piece to capture it, provided that the space immediately beyond (where the Zag winds up) is empty. The Zag may not move orthogonally when not capturing, however.

I made up the name and the move of this piece especially for this game. The Zag is the diagonal counterpart of the orthogonally moving Zig.

Zebra (Z)

• Promoted Guard

Because of its long reach, the Zebra is fairly weak as leapers go; it has relatively few squares on the board from which it exercise its full power.

Zig (Zi)

• Promoted Firzan

The Zig moves and captures like a Wazir or Dabbaba; in addition, it may leap a diagonally adjacent hostile piece to capture it, provided that the space immediately beyond (where the Zig winds up) is empty. The Zig may not move diagonally when not capturing, however.

I made up the name and the move of this piece especially for this game. The Zig is the orthogonal counterpart of the diagonally moving Zag.

Rules

Promotion Rules

Victory Conditions

• Your King or Emperor is captured.

• Your King or Emperor is bared; that is, your only remaining piece is the King or Emperor.

  Unlike the usual version of this Bare King rule, there is no provision for a draw if you can immediately bare the opponent's King or Emperor; as soon as you are down to one piece, you lose, period.

• It is your turn and you have no legal move.

It is not, strictly speaking, illegal to move your King or Emperor into check. It is certainly foolish, though.

Note that these rules make stalemate a loss for the stalemated player, not a draw.

The Bare King rule means that when you are reduced to 2 pieces, both are effectively royal.

You can move your King into what looks like check if it captures your opponent's next-to-last piece, since you win the game before your opponent can recapture (the Zillions file I made doesn't permit this, since it thinks the game ends with checkmate rather than actual capture of the royal piece, but fortunately, this situation is rarely important in practice).

Repetition

It is illegal to make a move that causes a given game situation to occur a 3rd time in the same game. Two game situations are considered the same if the same types of pieces are in the same places and it is the same player's turn to move.

Specifically, repetition does not result in a draw; one player must make a move that leaves the cycle of repeating moves. When a player is to move but has no move that would not cause an illegal repetition, that player loses the game.

As an example of this repetition rule, consider how it would apply to a trivial game played on a 2 by 3 board, with rules the same as Scirocco except as specified. The game starts with a White King on a1 and a Black King on b3; in this microscopic chess variant, there is no Bare King rule (so the game is not already over at the beginning). This game must proceed as follows:

1. K-b1 K-a3
2. K-a1 K-b3 ; 2nd occurrence of initial position
3. K-b1 K-a3
4. K-a1

At this point, the move 4. ... K-b3 would recreate the initial position again; this would be the 3rd occurrence of that position, so the move is not legal. If this variant allows a King to move into check, Black must do so (with 4. ... K-a2 or 4. ... K-b2), in which case White will capture the King and win on the next move; if this variant does not allow moving into check, then Black has no legal move, and loses immediately.

Draws

If you have read the above rules carefully, you will realize that any game of Scirocco played to the bitter end cannot result in a draw. Even if neither player is checkmated or reduced to a single royal piece, the repetition rule ensures that the game will end, because the number of possible board positions is finite, and each position cannot occur more than twice. When no more positions are available, the player whose turn it is will lose.

Players may, however, agree to a draw if they are so inclined.

It is conceivable that both players may be reduced to a small number of weak but highly mobile pieces, so that the repetition rule must be invoked to determine who wins the game. For example, each player might have an Emperor and a Harpy. In this case, the 2 sides can wander aimlessly about the board for an astronomical number of moves before the repetition rule finally cuts off one player or the other, and figuring out which player will lose is an absurdly difficult proposition (I think. I haven't actually tried to prove this; there may be some mathematical shortcut that makes the winner in this case obvious). In such a case, unless the players are particularly pigheaded, they should agree to the draw.

I'm not going to pin down exactly when agreeing to a draw is advisable, but if I hear of anyone playing a game of Scirocco that lasts thousands of moves, I will be very disappointed.

Notes

Playing Tips

Scirocco has not been extensively play-tested. In fact, I have played it only against Zillions (and I have let Zillions play against itself). However, so far, the game seems to play pretty much the way I envisioned it. It will, however, be interesting to see how 2 human players do with the game, since Zillions definitely does not play the way a human being would.

Scirocco typically opens with both sides advancing their weak pieces (Pawns, Guards, and Firzans) to try control the middle ranks of the board. The Dervish plays an important role by giving these pieces a little extra mobility. The center files appear to be less critical than in Orthochess, probably because there are more files, and because so many of the pieces are short-range and would not gain mobility by being in the exact center of the board.

The opening may see an exchange or two (the Camels are often exchanged in the rotationally symmetric setups), but exchanges don't usually begin in earnest until after around move 20. By this time, stronger pieces will have been moved in to back up the weak pieces advanced in the opening.

The midgame consists of a long series of positional posturings and occasional exchanges (of pieces that are close in value, if the players are both good). Eventually (somewhere around move 50 to 80 or so) the board has been significantly cleared, and one or both players can make a breakthrough into the promotion zone.

Zillions plays a pretty good middlegame (much better than I do, if I crank its thinking time up; but then, I'm a pathetic chess player). However, Zillions doesn't seem to have much of a sense of the value of promotion, and rarely sacrifices material to achieve a breakthrough. A human player who hasn't lost too much material in the middlegame can take advantage of this weakness in Zillions to make an early breakthrough with a strongly promoting piece to mate the computer's King. Acquiring a Genie, Lioness, or Queen is often decisive.

I hope that a game between 2 competent, aggressive human players will often end in a tight mating race. If some decent players are willing to try the game, then we'll see.

Most games of Scirocco seem to last around 100 moves, give or take a couple of dozen. Games ending in bared King (or bared Emperor) and games ending in mate both occur pretty frequently.

Notation

• Simple moves: Because the abbreviations of many piece names are 2 characters, it looks less confusing to me to use a dash consistently between a piece abbreviation and the piece's destination (e.g., Wa-a7 rather than Waa7), but leaving out the dash does not actually introduce any ambiguity.
• Relayed moves: These can be recorded as normal moves; it should be obvious from context when a move was relayed.
• Promotions: You can record these as unpromoted-destination=promoted or Shogi-style as unpromoted-destination+, since it is always obvious from context what a piece promotes to.
• Igui captures: I suggest using the x! notation usual for Chu Shogi; e.g., Gex!c6 for a Genie capturing a Pawn on c6.
• Hop-captures: This can be notated as a normal capture or normal move, since there is no ambiguity (a Zig or Zag always winds up one square beyond where the capture occurred); however, a notation showing both the capture square and destination square (e.g., Zixd4-e5) may avoid momentary confusion in the mind of a reader.

Last revised by H. G. Muller.