Check out Janggi (Korean Chess), our featured variant for December, 2024.

This page is written by the game's inventor, Roberto Lavieri.

Epsilon Eridani

By Roberto Lavieri

Introduction

EPSILON ERIDANI is the name of a yellow star (almost surely with at least one planet orbiting it!), in the same constellation of the blue, big and bright ALPHA ERIDANI (ACHERNAR). This game is also related to the game Achernar, (is Epsilon Eridani the little brother?) with some differences, one of which is the board size (Epsilon Eridani is played on a 44-square board). The pieces and rules mark other differences with Achernar. This game has various peculiarities, one of these is the potential strong movement capabilities of pieces, balanced with the presence of the Reducer. All pieces (except the King) in this game are cannibals, ie they can take friendly pieces. This characteristic may be used in some situations, but there is a "PROMOTION BY COMPENSATION" rule that is compensatory when a minor piece - a Soldier or an Overtaker - captures a friendly piece. Many pieces have the NON-CAPTURING **CH** movement, that is, these pieces can go from a colored file to any other square on the next or previous parallel file of the same color. Soldiers and promoted Soldiers can move with the **H** movement, like a horizontal Rook. But each piece has its own movement and method of capture. And Epsilon Eridani also features an important and nice piece which cannot capture: the REDUCER, which can REDUCE the abilities of adjacent pieces, to only ONE-SQUARE movement according to the original piece movement or method of capture. (Additionally, a reduced Soldier can´t move with the **H** movement.) A Reducer MAY NOT be captured by an enemy piece other than the King or the GRAND-HORSE.

Movements and general rules

The pieces in Epsilon Eridani have strong movement capabilities, but their capturing power is only a little higher than in Chess, power and movements dynamic are balanced with the presence of the Reducer. Some of the pieces (with exceptions) have the non-capturing **CH** movement, that is, they can go from a colored file to any other square on the next or previous parallel file of the same color. Some pieces have too the **H** non-capturing movement, moving horizontally as a Rook. But each piece has its own capturing movement. Pieces other than the King are cannibals, that is, they can take friendly pieces. In Epsilon Eridani there is a rule that allows a compensation when a minor piece - a Soldier or an Overtaker - captures a friendly piece: The capturing piece can "promote by compensation", a Soldier to Grand Soldier and an Overtaker to Diamond-Warrior.
The Reducer cannot capture. Instead of that, it can reduce the abilities of adjacent pieces, to only one-square movement, according to the piece movement or method of capture. A Reducer may not be captured by an enemy piece other than the King or Grand-Horse. A Grand-Horse can capture the Reducer only at distance, when adjacent it can´t capture the Reducer. Soldiers can promote to Grand-Soldiers when they reach the last file. There is neither castling nor en-passant rule.

Board and Setup

The Board is 5x9 with a hole in the middle square, with squares colored with three colors. The Soldiers start on the third rank, the Overtakers and Diamond-Warrior on the second rank, and the Reducer, Grand-Horse, King, Grand-Bishop and Grand-Rook on the first rank.

Pieces

 

S 

 

 

The Soldier moves without capturing one square orthogonally forward, one square diagonally forward or with the HORIZONTAL(H) movement; it captures one square diagonally forward. If reduced, it loses the H movement. A Soldier on the THIRD (White) or SIXTH (Black) FILE can move two squares forward. When a Soldier reaches its last file , it can move with the CHANGE(CH) movement from any square on the last file. On the last File, it can promote to Grand-Soldier. The Soldier may not capture the Reducer.

 

GS

  

The Grand-Soldier moves and captures one step diagonally forward, or one step orthogonally forward or backward. It can move without capturing with the CH and the H movements. The Grand-Soldier may not capture the Reducer.

 

DW

 

The Diamond-Warrior is a one-square diagonal leaper and a two-square diagonal and orthogonal leaper. It can also move without capturing with the CH movement. When adjacent to the enemy Reducer, it can only move one square diagonally. The Diamond Leaper may not capture the Reducer.

 

O

 

The Overtaker moves without capturing as a King, and with CHANGE and HORIZONTAL movements, it takes by jumping (like an omni-directional Draughtsman), jumping an enemy piece diagonally. When adjacent to the enemy Reducer, it can only move one square without capturing. The Overtaker may not capture the Reducer.

 

H

 

The Grand-Horse moves and captures as a Chess Knight or with a single orthogonal step. It can move without capturing with the "CH" movement. The Grand Horse may capture the REDUCER when it is not adjacent to it, whith its Knight movement.

 

B

 

The Grand-Bishop moves and captures diagonally as a FIDE Bishop, but it can also move and capture with a three-square diagonal leap, and it can move without capturing to the next or previous row of the same color (CH movement), and horizontally it is also allowed a non-capturing Rook's movement (H movement), it is also capable of doing orthogonal one-step non-capturing movements. When moving diagonally, the Grand-Bishop captures a (friendly or enemy) piece on the square it is moving to. When adjacent to the enemy Reducer, it conserves only its one-step moving and capturing capabilities. It may not take the Reducer.

 

R

 

The Grand-Rook is an orthodox FIDE-Rook which has also CH moves. When adjacent to the enemy Reducer, it moves only one step orthogonally. It may not take the Reducer.

 

Rd

 

The Reducer moves as a FIDE Queen. It cannot capture any piece. It has instead the ability to Reduce the move and capture abilities of adjacent enemy pieces. An enemy piece adjacent to the Reducer can only move or capture with ONE-SQUARE movement according to the piece capabilities. The Reducer may only be captured by the Grand-Horse when they are not adjacent, or by the King. It may not be captured by another piece. It is a nice piece, and it is an important piece in the game.

 

K

 

The King is the royal piece. It moves and capture with a single step in all eight directions with FIDE King movement. The King can capture and it is immune to the REDUCER. The King is the only piece which may not capture friends.

 

 

How to win

Win condition: Checkmate the opposite King, or reduce enemy pieces to only TWO. The game is a DRAW by accord between the players, or after 35 moves without captures or promotions.

 

Playing Tips

Material advantages are not as important as in FIDE Chess, but they are still important. The game is very tactical, strategy is usually deep in the middlegame, but much clearer in the endgame. Use well the Reducer. It is a great piece although it can´t capture. All the pieces are relatively powerful, including the Soldiers. As a guide, this is my subjective evaluation of the pieces (FIDE PAWN=1): SOLDIER= 1.8; OVERTAKER= 3.4; GRAND-SOLDIER= 4.7; DIAMOND-WARRIOR= 6.0; GRAND-BISHOP= 7.0; GRAND-HORSE= 7.6; GRAND-ROOK= 7.8; REDUCER= 9.5. Major pieces have great movement capabilities, but they are not extremely powerful as attacking pieces. Although the pieces are more powerful than Chess pieces, the Reducer makes checkmating the enemy King usually a little more difficult than in Chess. You may take your own pieces in some situations where you can attack two or more important enemy pieces with the capturing cannibal, when promotion by compensation is desirable, or in some attacks against the King. The game dynamic should appear a little strange at first but once assimilated it is really enjoyable, and tactics are usually cool. Normally, a good game is not too short, the average is about 40-60 moves per player.

Computer Play

You can play Epsilon Eridani if you have installed on your Computer a Registered version of ZILLIONS OF GAMES (the 35 moves without progress rule for a draw was not implemented). You can Download the EPSILON ERIDANI ZRF and graphics here. (Author: Roberto Lavieri)

Text and graphics by Roberto Lavieri. Slightly edited by Antoine Fourrière.