The Chess Variant Pages

Thinktank Chess

By Frank Maus

Introduction

Thinktank Chess is variant of International Chess where all of the pieces other than the King and Queen move differently when capturing from how they move when not capturing. Such pieces are called are called divergent or sniper pieces. Thinktank Chess was developed by Frank Maus in 1927, and is also called Sniper Chess.

Board and Setup

In the graphics for the back-rank pieces other than the King and Queen, the top of the pieces indicates how the piece moves without capturing, and the bottom of the piece how it captures. In the letter codes for those pieces, the first part of the code indicates how the piece moves without capturing, and the second part how it captures. Likewise with the names, the first part of the name indicates how the piece moves without capturing, and the second part how it captures. Thus, the Rookni, with a code of R/N, moves like a Rook when not capturing, but moves to capture like a Knight.

Thinktank Chess initial setup.
White:
Rookni (R/N): a1
Kniroo (N/R): b1
Biskni (B/N): c1
Queen (Q): d1
King (K): e1
Bishroo (B/R): f1
Knibis (N/B): g1
Roobis (R/B): h1
Pawns (P): a2 b2 c2 d2 e2 f2 g2 h2
Black:
Rookni (R/N): a8
Kniroo (N/R): b8
Biskni (B/N): c8
Queen (Q): d8
King (K): e8
Bishroo (B/R): f8
Knibis (K/B): g8
Roobis (R/B): h8
Pawns (P): a7 b7 c7 d7 e7 f7 g7 h7
  +---+---+---+---+---+---+---+---+
8 |r/n|n/r|b/n|:q:| k |b/r|n/b|r/b|
  +---+---+---+---+---+---+---+---+
7 |:p:| p |:p:| p |:p:| p |:p:| p |
  +---+---+---+---+---+---+---+---+
6 |   |:::|   |:::|   |:::|   |:::|
  +---+---+---+---+---+---+---+---+
5 |:::|   |:::|   |:::|   |:::|   |
  +---+---+---+---+---+---+---+---+
4 |   |:::|   |:::|   |:::|   |:::|
  +---+---+---+---+---+---+---+---+
3 |:::|   |:::|   |:::|   |:::|   |
  +---+---+---+---+---+---+---+---+
2 | P |:P:| P |:P:| P |:P:| P |:P:|
  +---+---+---+---+---+---+---+---+
1 |R/N|N/R|B/N| Q |:K:|B/R|N/B|R/B|
  +---+---+---+---+---+---+---+---+
    a   b   c   d   e   f   g   h

Rules

The game is conducted by rules of International Chess with the following changes:

The game is won by checkmating a player's King.

The Pieces and their Movements

The King, the Queen, and the Pawns move as normal. The divergent back-rank pieces move as indicated in the following table.

Piece Starting Locations Description
Rookni
R/N
a1
a8
The Rookni moves like a Rook when not capturing, but moves like a Knight when capturing.
Kniroo
N/R
b1
b8
The Kniroo moves like a Knight when not capturing, but moves like a Rook when capturing.
Biskni
B/N
c1
c8
The Biskni moves like a Bishop when not capturing, but moves like a Knight when capturing.
Bisroo
B/N
f1
f8
The Biskni moves like a Bishop when not capturing, but moves like a Rook when capturing.
Knibis
N/B
g1
g8
The Kniroo moves like a Knight when not capturing, but moves like a Bishop when capturing.
Roobis
R/B
h1
h8
The Rookni moves like a Rook when not capturing, but moves like a Bishop when capturing.

Allthought Chess

A variant of Thinktank Chess that Maus invented is Allthought Chess, which is played just like Thinktank Chess, except that the Pawns are replaced by Anti-Pawns, which are Berolina Pawns (move diagonally forward without capturing and capture straight forward).

Equipment

Maus intended these games to be played using a regular Chess set. He suggested tying ribbons around the Kingside pieces to distinguish them from the Queenside pieces.

Notes and Comments

There are other games with divergent pieces, for example all variants that use FIDE Pawns or Xiangqi Cannons have divergent pieces. Some other variants built around divirgent pieces are A.J. Winkelspecht's game Divergent Chess, Michael Howe's game Asymmetric Chess, and Christian Freeling's game Loonybird.

Given the names of these games -- Thinktank and Allthought -- one suspects that Maus thought of these games as a sort of mental exercise. Indeed, playing these variants with a regular Chess set might well give one some of the same mental workout some people enjoy from Ultima.

Zillions of Games

There is an implementation of Thinktank Chess and Allthought Chess for Zillions of games. You can download it here:



Written by Peter Aronson and Sergey Sirotkin.
WWW page created: December 18th, 2001.