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This page is written by one of the game's inventor, Edward Jackman.

Unachess and variants

by Edward Jackman ((email removed contact us for address) meNet.Com)

There is an article on Jeff Miller and his invention Unachess in this month's (March 1995) issue of 'Interview Magazine'. According to Jeff, the article is largely bogus -- most of what are supposed to be quotes aren't quotes at all, but it's still a nice multipage article.

At this point we think that white may have an unbeatable game by opening with the queen followed by the king (something like 1. Q*b2 or c3 followed by dropping the king to some safe place) -- if this is true then the game is dead. Any thoughts?

Here are the rules to the game and some variants:


Unachess

Invented by Jeff Miller

with help from Edward Jackman
all rights reserved by Jeff Miller
Official concise rules

Same as standard orthochess except:

  1. The board is initially empty and each player has the normal complement of 16 pieces in reserve.
  2. During a turn, a player must do one of three things:
    1. place a piece from in hand on an empty square on the board
    2. move a previously placed piece to an empty square
    3. move a previously placed piece onto a square occupied by an opposing piece, capturing it.
  3. Pawns may be entered on the second, third or fourth rows only. Pawns entered on the second row have the power of an initial double move and may be captured en passant as in standard chess.
  4. Castling is allowed if King and Rook are on traditional squares, and all the normal conditions required for castling exist.
  5. A player's King must be placed before being allowed to make any capturing moves. A piece that controls the square that the enemy King occupies does not check it until the friendly King is entered onto the board. That is called 'quasi-check'. A player is under no compulsion to move out of quasi-check, and may even move into quasi-check. A player may legally move into quasi-check.

Variations played include:


Here are some Unachess variants that came about after many player suggestions that white had too large of an advantage and that the game was to 'sharp' -- once you were in trouble, odds are it's all over.

Unachess II

Invented by Edward Jackman
Based on Unachess by Jeff Miller

All the rules to Unachess apply with these important changes:

  1. A dropped piece may NOT be placed so that it attacks the enemy king, regardless of whether or not the friendly king is on the board yet, under ANY circumstances, even if it is the only way to escape mate.
  2. Castling and en passant are not allowed.

This variation is much more forgiving of errors in the opening than standard Unachess and games are longer and more orthochessish. It is quite common for the initiative to go back and forth many times -- as opposed to Unachess where it is unlikely to change hands more than once, if at all.

Highly suggested variations:


Parachute chess (Unachess III)

Invented by Edward Jackman
Based on Unachess by Jeff Miller

All the rules to Unachess II apply with these important changes:

1. A dropped piece may not be placed so that it attacks ANY enemy piece under ANY circumstance.

The thinking behind this game is that if you are parachuting into a battle, you are helpless until you land. It is quite possible to have be unable to enter a Queen legally later in the game and quite likely to be unable to enter any piece at all to specific squares.

I can't say whether Unachess II or Parachute chess is the better game yet, but so far I like Parachute chess best.


Unashogi

Invented by Edward Jackman
Based on Unachess by Jeff Miller

Same as standard Shogi except:

  1. The board is initially empty and each player has the normal complement of 20 pieces in reserve.
  2. During a turn, a player must do one of three things:
    1. place a piece from the reserve on an empty square on the board
    2. move a previously placed piece to an empty square
    3. move a piece to a square occupied by an opposing piece, capturing it.
  3. A player may not make a capture until her/his own king is on the board. Your pieces have no real power of check on the opposing king until your own king is placed. Your opponent can legally place his or her king right next to your promoted Rook if your king is still in hand. There is no additional rule governing when you must enter your king. If a piece is checking the opposing king, but the friendly king has not been placed, that is called quasi-check. A player is under no compulsion to move out of quasi-check.

Variations

This last game is completely untested.

I'd be glad to hear comments, suggestions, ideas.

Edward Jackman ((email removed contact us for address) meNet.Com)


Written by Edward Jackman.
WWW page created: 1995. Last modified: June 23, 1998.