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


By Roberto Lavieri



ACHERNAR is a nice game, a mix of the game ALTAIR and Western Chess, with a playability that is very enjoyable. The object of the game is to checkmate the enemy King. You can also win the game if you reduce enemy pieces to only TWO (the King and another piece). As in Altair, all pieces (except the King) in this game are cannibals, they can take friendly pieces (enemy pieces too, of course). This fact may be used eventually in some situations, when it is desirable according to the position and your purposes. The board has squares colored with three colors in horizontal bands. Many pieces can move from a square to any square on the next or previous line of the same color. Pieces have great mobility, balanced with the presence of the REDUCER, a piece that can diminish the capabilities of other pieces.


Movements and general rules

Pieces in ACHERNAR have strong movement capabilities, but the capturing power is only a little higher than in Chess. Power and movement dynamics are balanced by the presence of the REDUCER. 

Some of the pieces (with exceptions) have the NON-CAPTURING **CH** movement. With CH movement, the piece can go from a colored file to any other square on the next or previous parallel rank of the same color. 

Many pieces also have the **H** non-capturing movement, moving as Rook over the horizontal colored line of squares. 

But each piece has its own capturing movements. 

There is a cool piece in this game that can't capture: THE REDUCER, an interesting piece that can REDUCE the abilities of adjacent pieces, to only ONE-STEP movement according to the piece movement or method of capture. A REDUCER CAN'T 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 when reach the last file to Grand-Soldiers. 

There is no castling or an en-passant rule


Board and Set Up


 The Board is 9x9, with squares colored with three colors: Blue, Yellow and Grey. Many pieces have similar BASIC non-capturing movements (with a few exceptions):

1.- Change of Horizontal file, moving from one colored horizontal line of squares to the immediately following or the immediately preceeding parallel line of squares of the same color. This is, a non-capturing move, and the piece can go to ANY position in the new line. ("CH" movement)

2.- Moving over the horizontal line, with a FIDE-Rook movement. ("H" movement)





Grand Soldier


A Soldier moves one square Orthogonally forward, one Diagonally forward, or with the HORIZONTAL (H) movement, and captures one diagonally forward. If Reduced, it loses the H movement. If in the THIRD (White) or SIXTH (Black) ranks, it can move two forward. When a Soldier reaches its last rank, it can move with the CHANGE (CH) movement from any square on the last rank. In the last rank, it can promote to Grand-Soldier (approximate subjective value: 2.2. Consider FIDE-Pawn=1)



Grand-Soldier moves and capture one step diagonally forward, or one step orthogonally forward or backward. It can move without capture with the CH and the H movements (subjective value: 5.0)



Overtaker: Moves as King without capture, and with CHANGE and HORIZONTAL movements, it captures by jumping (like piece of draughts but in all directions). When adjacent to the enemy reducer, it can't capture and only can move one position with King non-capture movement. The Overtaker can't capture the Reducer. (value: 3.5)

Grand Horse


Grand-Horse: Moves and captures as Knight in Chess (in "L") and it can move and capture in a single orthogonal step. It can move without capturing with the "CH" movement. The Grand Horse can capture the REDUCER, when not adjacent, with its Knight movement. (value: 6.5)




Queen: orthodox FIDE-QUEEN move. When reduced, Queen retains its one-step capabilities. It can't take the Reducer. (value= 8.5)

Grand Bishop



Grand-Bishop: can move and capture diagonally as a FIDE Bishop. The piece also leaps EXACTLY three squares diagonally, moving and capturing (it can leap over pieces exactly three steps). It can also move to the next parallel rank of the same color without capturing (CH movement), and on the horizontal rank it is on with rook non-capturing movement (H movement). It also is capable of doing orthogonal one-step non-capturing movements. When moving diagonally, the Bishop captures a piece (friend or enemy) on the square its moving to. When adjacent to an enemy Reducer, it conserves only it's one-step capabilities moving and capturing. It can't take the Reducer. (value: 7.0)

Grand Rook



Grand-Rook: FIDE-Rook orthodox moves plus CH moves. When adjacent to the Reducer, the Grand-Rooks moves only one step orthogonally. It can't capture the Reducer. (value: 7.2)





A REDUCER moves as a FIDE Queen. It can't capture any piece. Instead of this, it has the ability of REDUCE the movement and capture abilities of adjacent enemy pieces. An enemy piece adjacent to the Reducer can only move or capture with ONE-STEP movement according to the piece capabilities. The Reducer can only be captured by the Grand-Horse when they are not adjacent, or by the King. It can't be captured by another piece. It is a nice piece, and it is an important piece in the game. (value: 9.5)



King is the royal piece. The King 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.



Win condition: Checkmate the opposite King, or reduce enemy pieces to only TWO.


Playing Tips

Computer Play

Now you can play ACHERNAR if you have installed on your Computer a Registered version of ZILLIONS OF GAMES. You can Download the ACHERNAR ZRF and graphics at the link below. (Author: Roberto Lavieri)