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Antarctic Chess or Predators and Penguins


Christmas has just passed and we have had our first major fall of snow - so something south-polar seems appropriate.

The initial inspiration came from a magazine article about a book on snowflakes and to this was added ideas arising from recent media interest in Penguins.  The result is a game which offers several two-player and multi-player possibilities:
    1. *2-player unequal forces (2U) -  one player controls the Predator Pack, the other controls three Penguin Colonies.
    2. *2-player small equal forces (2S) - each player controls a single combined group of Predators and Penguins.
    3. *2-player large equal forces (2L) - each player controls 3 combined groups.
    4. 3-player small equal forces (3S) - each player controls a single combined group.
    5. 3-player large equal forces (3L) - each player controls 2 combined groups.
    6. 4-player unequal forces (4U) - one player controls the Predator Pack, the others each control one Penguin Colony.
    7. *6-players equal forces (6E) - each player controls a single combined group of Predators and Penguins.
    8. 7-players unequal forces (7U) - one player controls the Predator Pack, the others each control one Penguin Colony.
* - indicates options detailed below.

Setup

The Board

This consists of 295 hexes arranged in the shape of a snow crystal.  The image to the right shows this original snow crystal† superimposed on the resulting game board.  The hexes are shaded in one of three colours, except for the central hex which is white. 

The board can also be thought of as representing pack-ice in the south-polar seas.  The Penguins start at the melting, thin outer edge and their aim is to reach the safety of the centre.  The  Predators aim is to stop them.

In game terms a player controlling a Penguin colony or a Combined group wins by moving their Emperor Penguin onto the central white hex.  A player controlling a Predator pack wins by capturing all Emperor Penguins. 

In games with equal forces where players control one or more combined groups, a player may also win by being the only one with an Emperor penguin still on the board.
snow crystal and board
†permission for use of the snow crystal image kindly given by Kenneth G. Libbrecht, Professor of Physics at Caltech.

Pieces

For the Penguins we have:  Emperor, King, Gentoo, Rockhopper and Fairy.
and for the Predators: Orca, Leopard (Seal), Elephant (Seal), Petrel, and Skua.

A Penguin Colony consists of: 1 Emperor, 2 Kings, 2 Gentoos, 3 Rockhoppers, and 4 Fairies.

When playing against 3 Colonies the Predator Pack consists of: 1 Orca, 2 Leopards, 2 Elephants, 2 Petrels, and 6 Skuas.
When playing against 6 Colonies it is doubled to: 2 Orcas, 4 Leopards, 4 Elephants, 4 Petrels, and 12 Skuas.

A Combined Group consists of a Colony augmented by 1 Orca, 1 Leopard, 1Elephant, 2 Petrels, and 2 Skuas.

In the file for Zillions-of-Games two piece-sets are provided.
In one the pieces are represented by hexagonal tiles with a different base colour for each type of piece and a different border colour for each player.  The initial letter of the piece is also shown on the tile, upper-case for Penguins, lower-case for Predators. (See images under "Initial Arrays" below right.)
In the other the pieces are represented by icons in the shape of each animal.  Each Piece is partially coloured to indicate the player while each Penguin also has a "waistcoat" coloured according to type.  (See images under "Initial Arrays" below left.)

Initial Arrays

Start Position - 2U - Icon piece-set
Start Position - 6E - Tile piece-set
start position - icons
start position - tiles
Start Position - 2S - Icon piece-set
Start Position - 2L - Tile piece-set
start position - icons start position - tiles

Rules

Summary
Variant
Code
Players
Forces
Win Conditions
2-player unequal forces 2U
Predators
1 Pack
Capture all the Emperors
Penguins
3 Colonies
Place an Emperor on the central hex
2-player small equal forces 2S
Gold
1 Group
Place an Emperor on the central hex or capture your opponent's Emperor
Red
1 Group
2-player large equal forces 2L
Gold
3 Groups
Place an Emperor on the central hex or capture all 3 of your opponent's Emperors
Red 3 Groups
6-players equal forces 6E
Gold, Cyan, Brown, Green, Blue, Tan
1 Group each
Place an Emperor or King on the central hex or be the only player with an Emperor or King on the board.



Movement

Orca iconorca tileOrca
The Orca combines the move of the orthodox Queen and Knight.

It can slide in any direction any number of hexes, but may not leap over pieces that are in its path. It can also move like a knight when it may leap over pieces. A knight's move consists of a a diagonal step followed by an orthogonal step in the same general direction; alternatively the orthogonal step can be made first followed by a diagonal step in the same general direction.

The Orca's moves are shown in the image to the right.
- blue dots are reached by sliding diagonally
- yellow dots are reached by sliding orthogonally
- magenta dots are reached by a knight's move

A captured Orca may be brought back into play. See the Returns section below.

Orca move
leopard iconLeopard tileLeopard
The Leopard moves like an orthodox Queen, combining Bishop and Rook.

It can slide in any direction, diagonally or orthogonally, any number of hexes, but may not leap over pieces that are in its path.

The Leopard's moves are shown in the image to the right.
- blue dots are reached by sliding diagonally
- yellow dots are reached by sliding orthogonally

A captured Leopard may be brought back into play. See the Returns section below.
Leopard move
Elephant iconElephant tileElephant
The Elephant combines the move of the orthodox Rook and Knight.

It can slide orthogonally any number of hexes, but may not leap over pieces that are in its path. It can also move like a knight when it may leap over pieces.

The Elephant's moves are shown in the image to the right.
- yellow dots are reached by sliding orthogonally
- magenta dots are reached by a knight's move

A captured Elephant may be brought back into play. See the Returns section below.
Elephant move
Petrel iconPetrel tilePetrel
The Petrel combines the move of the orthodox Bishop and Knight.

It can slide diagonally any number of hexes, but may not leap over pieces that are in its path. It can also move like a knight when it may leap over pieces.

The Petrel's moves are shown in the image to the right.
- blue dots are reached by sliding diagonally
- magenta dots are reached by a knight's move

A captured Petrel may be brought back into play. See the Returns section below.
Petrel move
Skua iconSkua tileSkua
The Skua combines the move of the orthodox Knight with an orthogonal step.

It can step one hex orthogonally or may leap like a knight.

The Skua's moves are shown in the image to the right.
- green dots are reached by stepping orthogonally
- magenta dots are reached by a knight's move

Skua move
Emperor iconEmperor tileEmperor
The Emperor combines the move of the orthodox Knight with a full double-step.

It may move one or two steps diagonally or orthogonally or may leap like a knight. It may not leap over other pieces except when making a knight's move.

The Emperor's moves are shown in the image to the right.
- orange dots are reached by stepping diagonally
- green dots are reached by stepping orthogonally
- magenta dots are reached by a knight's move


Emperor move
King iconKing tileKing
The King moves with a full triple-step.

It may move one, two, or three steps diagonally or orthogonally.
It may not leap over other pieces.

The King's moves are shown in the image to the right.
- orange dots are reached by stepping diagonally
- green dots are reached by stepping orthogonally

King move
Gentoo iconGentoo tileGentoo
The Gentoo moves with a full double-step.

It may move one or two steps diagonally or orthogonally.
It may not leap over other pieces.

The Gentoo's moves are shown in the image to the right.
- orange dots are reached by stepping diagonally
- green dots are reached by stepping orthogonally

Gentoo move
Rockhopper iconRockhopper tileRockhopper
The Rockhopper moves with a full single-step.

It may move one step diagonally or orthogonally to an adjacent hex.

The Rockhopper's moves are shown in the image to the right.
- orange dots are reached by stepping diagonally
- green dots are reached by stepping orthogonally


Rockhopper move
Fairy iconFairy tileFairy
The Fairy moves with an orthogonal single-step.

It may move one step orthogonally to an adjacent hex.

The Fairy's moves are shown in the image to the right.
- green dots are reached by stepping orthogonally


Fairy move

Returns

The Orca, Leopard, Elephant and Petrel can all be brought back into play for their original owner by being placed onto a hex in that player's return area. This return area consists of those hexes occupied by the player's Predators at the start of the game.

The image on the right illustrates the return areas for variant 6E. The hexes that are in a player's return area are marked with a dot in the relevant player's colour.

Returns are subject to the following rules:
  • the return of a piece by player constitutes that player's turn. No other moves may be made that turn by the same player.
  • the returning piece must be placed onto an empty hex in the player's return area. Capturing with a returning piece is not permitted.
  • the returning piece will undergo a transformation according to the following scheme:
    • Orca => Leopard
    • Leopard => Elephant
    • Elephant => Petrel
    • Petrel => Skua
    In other words a returning piece suffers a demotion as the price for its return.

return areas

Notes

The Board

The board was constructed by joining 3 smaller boards.

At the centre is a 5-hex per side board.  This is surrounded by 6 boards with 3-hexes per side and each of these has a 2-hex per side board on each of its 3 outer corners.

As well as conforming to the shape of a snow crystal the inner part of the board corresponds with the fractal curve known as a Koch Snowflake. The images below show a Koch Snowflake produced by the xfractint program, and the same Snowflake superimposed on the game board

Koch Snowflake
Snowflake on board


This 'user submitted' page is a collaboration between the posting user and the Chess Variant Pages. Registered contributors to the Chess Variant Pages have the ability to post their own works, subject to review and editing by the Chess Variant Pages Editorial Staff.


By Graeme C Neatham.
Web page created: 2007-01-30. Web page last updated: 2007-01-30