# Rococo

by

### Peter Aronson and David Howe

 Introduction Rules Board and Setup The Pieces and their Movements Notes and Comments Equipment Variants: Rococo with Pushme-Pullyus Rococo with Mirror Arrays Rococo with Enhanced Withdrawers Computer Play Also see: Illustrated Guide showing how the Rococo pieces move and capture. Ultima, Robert Abbott's game that Rococo was based on.

## Introduction

In his article, What's Wrong with Ultima (originally published in Michael Keller's WGR), Robert Abbott complains that his game Ultima favors the defense over the attack, and is lacking in clarity. Rococo started life as a revision of Ultima designed to cure these problems. The result, however, is rather far from Ultima, but still seems to be an interesting game in its own right, where attack is stronger than defense, and that possesses reasonable clarity.

## Rules

The rules of Rococo are identical to those of International Chess, except when noted below. The largest general rules change is that the object of the game is to capture the opposing King, not to checkmate it. Also, a player unable to move or who causes three time repetition loses as well.

The 36 outer squares of the 10 x 10 Rococo board are marked in the diagram below. These marked squares on the edge of the board are edge squares, and a move may only pass over or end on an edge square if it is necessary for a capture. (Or in other words, a piece may only end up on an edge square by making a capturing move that would not be possible without landing on the edge square.) This includes moves that start on edge squares. Also, only the minimal number of edge squares may be passed over in order for the capture to occur, thus:

A Long Leaper on x00 could capture an opposing piece on x3 by landing on x2 (assuming x8-x4 were empty), but may not capture an opposing piece on x3 by landing on x1 or x0.
(This is a clarification of the original rules which failed unambiguously to define the appropriate behavior in this case.) Moves that captures of multiple opposing pieces are not forbidden by edge squares -- the piece may move over as many edge squares as required for the capture. While a capture must be performed crossing as few as possible edge squares, when there is a choice among multiple possible captures, there is no requirement to choose the capture that crosses the fewest possible edge squares. The Swapper's swap move is considered a capture for purposes of edge squares.

To describe the rules for edge squares formally:

1. A move to an edge square (e) must involve a capturing move (c).
2. A capturing move (c) is distinguished by a capturing piece p on square s making a move that captures a set of one or more pieces P (p1, p2, ..., pN) on a set of particular squares S (s1, s2, s3, ..., sN).
3. A move to the particular edge square e must be the shortest move that would accomplish the particular capturing move c.
4. A move to the particular edge square e must be the only legal move (as restricted by the previous rule) that would accomplish the particular capturing move c.

## Board and Setup

Each player starts with 8 Cannon Pawns, 1 Advancer, 1 Chameleon, 1 Immobilizer, 2 Long Leapers, 1 Swapper, 1 Withdrawer and 1 King. The board is like the ring board from Jumping Chess, whose outer ring is special in that it can only be entered when required to to make a capture.
 +---+---+---+---+---+---+---+---+---+---+ 00 | * | * | * | * | * | * | * | * | * | * | +---+---+---+---+---+---+---+---+---+---+ 8 | * | I |:W:| L |:K:| C |:L:| A |:S:| * | +---+---+---+---+---+---+---+---+---+---+ 7 | * |:P:| P |:P:| P |:P:| P |:P:| P | * | +---+---+---+---+---+---+---+---+---+---+ 6 | * | |:::| |:::| |:::| |:::| * | +---+---+---+---+---+---+---+---+---+---+ 5 | * |:::| |:::| |:::| |:::| | * | +---+---+---+---+---+---+---+---+---+---+ 4 | * | |:::| |:::| |:::| |:::| * | +---+---+---+---+---+---+---+---+---+---+ 3 | * |:::| |:::| |:::| |:::| | * | +---+---+---+---+---+---+---+---+---+---+ 2 | * | p |:p:| p |:p:| p |:p:| p |:p:| * | +---+---+---+---+---+---+---+---+---+---+ 1 | * |:i:| w |:l:| k |:c:| l |:a:| s | * | +---+---+---+---+---+---+---+---+---+---+ 0 | * | * | * | * | * | * | * | * | * | * | +---+---+---+---+---+---+---+---+---+---+ x a b c d e f g h y
 White King (K): e1 Advancer (A): g1 Chameleon (C): e1 Immobilizer (I): a1 Long Leapers (L): c1 f1 Swapper (S): h1 Withdrawer (W): b1 Pawns (P): a2 b2 c2 d2 e2 f2 g2 h2 Black King (k): e8 Advancer (a): g8 Chameleon (c): e8 Immobilizer (i): a8 Long Leapers (l): c8 f8 Swapper (s): h8 Withdrawer (w): b8 Pawns (p): a7 b7 c7 d7 e7 f7 g7 h7

## The Pieces and their Movements

For those readers using graphic browsers, there is an animated illustration of each piece's move (other than the King's) available by clicking on the Animated Illustration link for each piece.

Most of the differences between Rococo and Ultima were the result of "fixing" the problems that Robert Abbott had pointed out with Ultima in one place or another:

• The edge squares were to avoid pieces being able to hide from Long Leapers around the edges. (The idea of adding edge squares that can only be entered in order to capture was borrowed from Jumping Chess.)
• The Cannon Pawns were a way to avoid the lack of clarity, edge weakness, and defensive advantage of Pincer Pawns (experience in general has shown that capture by interception favors the defense -- this is a problem with many attempts to recreate ancient Roman and Greek strategy games).
• The Swapper replaced the Coordinator, again to increase clarity.
• The Advancer was a high clarity piece added to replace some of the attack power lost by removing the Coordinator.

The other changes, such as the change in the array, victory by capture and Pawn promotion were the results of play-testing and experimentation.

In Ultima, no two pieces use the same form of capture. Purists might complain that Rococo breaks that rule, since both the King and the Cannon Pawns capture by replacement. Our view is that doesn't make it the same type of capture, since by that reasoning, capture by approach, withdrawal and overtaking are all forms of capture by relative movement. Direct replacement and leaping replacement are at least as different as those three forms of capture are from each other.

Is Rococo the "fixed" version of Ultima? Probably not. Instead, Rococo is a game in the Ultima family, with its own strengths and weaknesses. It is a very aggressive game, reminiscent of XiangQi in that position is often more important than material. It seems to be a game with a fair degree of clarity too.

## Equipment

Rococo can barely be played with a regular Western Chess set if there is enough of a border to the board so that pieces on edge squares can be placed just past the end of the grid. Rooks and Bishops will have to be distinguished, with one Rook being the Immobilizer and the other the Swapper, and one Bishop being the Withdrawer and one being the Advancer, and the Knights are the Long Leapers and the Queen is the Chameleon. It is certainly easier to play with an actual 10x10 board.

## Variants

### Rococo with Pushme-Pullyus

In developing his as yet unpublished game Supremo (a related project to Rococo), Fergus Duniho invented a piece that combined the capturing powers of an Advancer and a Withdrawer, which he called the Pushme-Pullyu, after a creature in Docter Dolittle. In this variant of Rococo, the Pushme-Pullyu replaces both the Advancer and the Withdrawer in the opening array.
 Piece Description Pushme-Pullyu The Pushme-Pullyu moves like a Queen, but never to an occupied square. If it moves directly away from an adjacent opposing piece, it will capture it like a Withdrawer. If it moves directly next to an opposing piece in its direction of movement, it will capture it like an Advancer. It may combine both types of capture in a single move. These captures are part of movement, and are not optional -- you can not move a Pushme-Pullyu directly away from an opposing piece and not capture it. Pushme-Pullyu's can enter edge squares when required to in order to capture by withdrawal. When on an edge square it may move to another edge square in order to capture by approach or withdrawal.

### Rococo with Mirror Arrays

Rococo is normally played with matching arrays for both sides, but it can be played with mirror arrays like Ultima. Black's back row is simply ordered: Swapper, Long Leaper, Advancer, Chameleon, King, Withdrawer, Long Leaper, Immobilizer, while White's back row is ordered in the usual way. This particular variant has gotten some club play in Venezuela.

### Rococo with Enhanced Withdrawers

In this variant, the Withdrawer -- the weakest of the backrow pieces -- is enhanced by making it immune to the effect of the Immobilizer. This still leaves it a fairly weak piece, but gives it an additional role in hounding the powerful Immobilizer. It does, however, make the piece asymmetrical in behavior with the its "partner" the Advancer.

## Computer Play

An implementation of Rococo has been written for Zillions of Games. You can download it here:

Written by Peter Aronson, graphics by David Howe.
WWW page created: May 19th, 2002.
WWW page modified: April 10th, 2005.
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