Portal chess

Portal chess is a chess variant which uses at least two fairy pieces called portals (or less commonly portholes). These pieces can be easily added by using poker chips, coins or other suitably sized objects. The game seeks to incorporate portals to allow pieces to teleport around the board. Apart from the portals and their ruleset, the game often plays like ordinary chess, including the en passant capture, castling, and promotion.

Versions

There are three versions of portal chess, created seemingly independently by three different people: David Howe in 1997,[1] Mike Hidden some time before 2008,[2] and Ian Buckley around 2012.[3] They all, however, contain the core dynamic of teleportation and special squares/pieces for this, as opposed to other variants which allow transportation at any point and/or any time.

Throughout the article, the symbol "" will be used to denote teleportation from one square to another.

David Howe version

a8 b8 c8 d8 e8 f8 g8 h8
a7 b7 c7 d7 e7 f7 g7 h7
a6 b6 c6 d6 e6 f6 g6 h6
a5 b5 c5 d5 e5 f5 g5 h5
a4 b4 c4 d4 e4 f4 g4 h4
a3 b3 c3 d3 e3 f3 g3 h3
a2 b2 c2 d2 e2 f2 g2 h2
a1 b1 c1 d1 e1 f1 g1 h1
A
a8 b8 c8 d8 e8 f8 g8 h8
a7 b7 c7 d7 e7 f7 g7 h7
a6 b6 c6 d6 e6 f6 g6 h6
a5 b5 c5 d5 e5 f5 g5 h5
a4 b4 c4 d4 e4 f4 g4 h4
a3 b3 c3 d3 e3 f3 g3 h3
a2 b2 c2 d2 e2 f2 g2 h2
a1 b1 c1 d1 e1 f1 g1 h1
B
Two-board variant with portals marked as corresponding numbers

In this version, there are two distinct playing areas linked by fixed portals. These areas can be either two separate boards or one board split down the middle (between the d- and e-files).

The rules that are different for this variant are:

  • Players alternate play between area A and area B. So play might go 1:Ae4 Ba5 2:Bh4 Ae5
  • If a player's piece is on a portal square when the player is playing in that board, he can declare an intent to teleport. He moves no other piece, and waits for his turn on the other board. He then teleports his piece but makes no other move, e.g. 20: 'Intends to teleport' qBe7 21: qAa4→Ba4 ...
  • Teleportation is always between areas, and also between corresponding squares (as close to the original coordinates as you can get).
  • If an opponent's piece occupies the target square when teleporting, it is captured normally. (qAa4→xBa4)
  • If a friendly piece is on the receiving teleporter when 'Intent' is declared, the move is still lost but with no teleportation. This could be used as a pass function. e.g. 20: 'Intends to teleport' qBe7 21: (no move, piece in way) Aa6 ...
  • If both players declare 'intent' in the same move, the teleportations are considered simultaneous. Thus no capture would occur between two pieces transporting together if they had just swapped places. e.g. 20: 'intent' 'intent' 21: Aa4→Ba4 Ba4→Aa4
  • A king can be left in check so long as the player can move it before it could be captured. Thus discovered checks from teleportations are allowed as the player can move their king away before their opponent next plays that Area.
  • All other rules are the same.

Mark Hidden version

abcdefgh
8
a8 black rook
b8 black knight
c8 black bishop
d8 black queen
e8 black king
f8 black bishop
g8 black knight
h8 black rook
a7 black pawn
b7 black pawn
c7 black pawn
d7 black pawn
e7 black pawn
f7 black pawn
g7 black pawn
h7 black pawn
a5 black circle
b5 black circle
e5 black circle
f5 black circle
c4 black circle
d4 black circle
g4 black circle
h4 black circle
a2 white pawn
b2 white pawn
c2 white pawn
d2 white pawn
e2 white pawn
f2 white pawn
g2 white pawn
h2 white pawn
a1 white rook
b1 white knight
c1 white bishop
d1 white queen
e1 white king
f1 white bishop
g1 white knight
h1 white rook
8
77
66
55
44
33
22
11
abcdefgh
The locations of the portals are marked with black dots.

The portals in this game are neutral yet mobile.

The number and starting location of these portals can be different when the game begins, but the image shows the standard set-up.

In this game the portal pieces move around by very specific rules.

  • A piece can only land on a portal square by attacking it. This means pawns move diagonally onto them, and knights must land directly on them.
  • A piece can not jump over a portal, except for the knight.
  • When a piece moves onto a portal, it must move to another portal. If no portals are free to do this, moving onto the portal is not allowed.
  • When a piece has moved through a portal, the portal it attacked moves to where the piece used to be. So the early move 2: f3xg4→c4 moves the portal from g4 to f3.
  • This also means portals may stack, and may be unstacked, but it is invalid to claim you have teleported from one stacked portal to another stacked portal (either where you have landed or elsewhere on the board).
  • Pawns must move normally onto the back rank to promote. So a pawn that has teleported there does not promote, as he is stuck in the portal.
  • Castling cannot occur if a portal is in the way, as the pieces cannot jump over it.
  • All other ordinary rules apply.

Ian Buckley version

abcdefgh
8
a8 black rook
b8 black knight
c8 black bishop
d8 black queen
e8 black king
f8 black bishop
g8 black knight
h8 black rook
a7 black pawn
b7 black pawn
c7 black pawn
d7 black pawn
e7 black pawn
f7 black pawn
g7 black pawn
h7 black pawn
a5 black cross
b5 black cross
c5 black cross
d5 black cross
e5 black cross
f5 black cross
g5 black cross
h5 black cross
a4 black circle
b4 black circle
c4 black circle
d4 black circle
e4 black circle
f4 black circle
g4 black circle
h4 black circle
a2 white pawn
b2 white pawn
c2 white pawn
d2 white pawn
e2 white pawn
f2 white pawn
g2 white pawn
h2 white pawn
a1 white rook
b1 white knight
c1 white bishop
d1 white queen
e1 white king
f1 white bishop
g1 white knight
h1 white rook
8
77
66
55
44
33
22
11
abcdefgh
Beginning layout of the board is standard. Possible sites for White's portal are marked with a dot, Black's possible spots are marked with a cross.
abcdefgh
8
a8 black rook
b8 black knight
c8 black bishop
d8 black queen
e8 black king
f8 black bishop
g8 black knight
h8 black rook
a7 black pawn
b7 black pawn
c7 black pawn
d7 black pawn
e7 black pawn
f7 black pawn
g7 black pawn
h7 black pawn
a5 black champion
e4 white champion
a2 white pawn
b2 white pawn
c2 white pawn
d2 white pawn
e2 white pawn
f2 white pawn
g2 white pawn
h2 white pawn
a1 white rook
b1 white knight
c1 white bishop
d1 white queen
e1 white king
f1 white bishop
g1 white knight
h1 white rook
8
77
66
55
44
33
22
11
abcdefgh
An example first move that would be annotated 1: Pe4 Pa5

This version of the game has player-controlled portals, which are linked to each other.

The rules for these portals are worked out as though they make the squares they cover into one square. In the set up to the right, a5 and e4 can be conceptualized as the same square.

The specific rules for portal use are as follows:

  • The aim of portal chess is the same as ordinary chess.
  • Players place their portals anywhere on the fourth row from the players side before commencing a game.
  • You can only move your colored portal.
  • A piece passes through portal unless the portal is blocked.
  • A piece can be blocked from entering a portal if a piece of the same color is on the other side.
  • A piece can take pieces by traveling through a portal.
  • Both portals cannot be occupied at the same time.
  • A piece can check/checkmate players using the portal.
  • A piece must exit the portal in the direction it traveled into the portal.
  • A portal can be moved onto a piece causing it to teleport, unless the other portal is occupied by any piece.
  • A player has a choice to move a chess piece or the portal piece in one turn, not both.
  • If your own chess piece is occupying a portal, you cannot pass through or rest on the other unoccupied portal with another one of your own pieces.
  • A piece can enter either portal regardless of color.
  • If both portals occupy the same square, it creates a black hole, which will remove any pieces in the eight squares around it from the game, as well as any piece on the black hole. This also locks both the portals in place so they can no longer be moved.
  • A portal can be moved regardless of whether it is occupied or not, the occupying piece does not move with the portal.
  • If a piece occupies one portal and a whole turn phase end without the piece moving from the teleporter it does not teleport.
  • A knight can jump over a portal piece.
  • A pawn can become a queen by using a portal, thus the move ...→h8=Q is valid.

References