Claustrophobia

Claustrophobia is played on a 5x8 board with 3 additional squares on each side - a total of 46 squares. These three squares constitute the palace, which initially holds the King, the Queen-Guard, and a Knight.

There is no castling for the king is already at a wing (in the palace), and the objective of the game is not just checkmate (which wins as usual), but to invade the palace of the opposing king with your king and capture the scepter. The scepter is located on the 3 squares of the palace, and can only be captured by the opposing king. The scepter must be protected at all cost for losing it forfeits the throne, power …everything.

Setup

Pieces

The Ninja Guard’s Moves

The Ninja Guard on c4 can capture all the pieces in the diagram. It can capture the pawn on a6 by jumping over the knight at b5. It can capture the pawn on b3 by moving to b3 or by jumping over the pawn and landing on a2. It can capture the knight on d5 by moving to d5 or it can capture both the knight and the pawn by jumping over to e6.

The Flying Bomber’s Moves

• The flying bomber eliminates an enemy piece by flying over it, and landing on the empty square immediately after it on the same orthogonal line. It cannot fly over or capture a second piece nor move beyond the first empty square after the enemy piece.
• The flying bomber can fly along any amount of empty squares (1-9) orthogonally, but not over any friendly pieces. This is identical to the movement of a rook.

• The Flying Bomber can fly over one friendly piece adjacent to it (left, right, up or down) and land on an empty square immediately after it. When it flies over a friendly piece adjacent to it, its range is limited to two squares.
• If an enemy piece is exactly 2 squares away orthogonally and no other piece is in-between, then the flying bomber can capture the usual way by flying over it and landing on any empty square after it. It can also capture by landing on the same square as the enemy like a Helicopter.
• If two enemy pieces lie on the same line,the first one adjacent to the bomber, and the next two squares away, then the flying bomber can eliminate both pieces by landing on the square of the second enemy piece. It cannot fly over the second enemy piece.
• Similarly, if there was a friendly piece in immediate vicinity of the bomber, and an enemy piece right after it, the Flying Bomber can fly over the friendly piece and destroy the piece right after by landing on the same square. Here too it cannot fly over beyond the enemy piece as it cannot fly over two pieces.
• The Flying Bomber needs at least one square to fly over for a bombing. e.g. it can destroy any enemy piece in its vicinity (1 square to left, right, up or down) by flying over it and landing on any empty square after it, but if a friendly piece occupies a square immediately after the enemy piece, no capture can be made.

The Extra-mobile sliding pawn

The Queen Guard

Moves over unused squares

The flying bomber at f7 is checking the king at f2 because it can capture by going to f1. Note that the unused squares do not hinder the movement of any pieces. The Ninja Guard on e4 is attacking the square g2 and so the king cannot go there. The flying bomber is threatening the knight on d7 as well. It can fly over, bomb the knight and land on c7. It can also eliminate the knight by going to d7 since it is exactly 2 squares away.

Rules

• There is no castling as the king is already in its palace where it is normally safe.
• In addition to checkmate, a side can also win by capturing the opposing king's scepter. Black's scepter is in the palace on f8,f7,or g7 and white's scepter on f1,f2,or g2.
  Only the king can capture a scepter, so for example,if the white king marches towards the black king's palace, black can use this opportunity to checkmate, or drive the white king away and march the black king towards the opposing palace.
• Pawns promote on the last rank to Queen-guard, ninja-guard,flying bomber or knight.
• The unused squares do not hinder the movement of any pieces.
• All rules governing draws including stalemate are exactly as in orthodox chess

Notes

• The flying bomber and a king cannot pry out an opposing king from its palace nor deliver mate.
• A lone ninja guard and a king can pry the opposing king out if, for white if the ninja guard is colorbound to black (same color as the extreme edge square g7 of black king's palace) or for black the ninja guard is color bound to white (correspond to g2).
• A knight cannot deliver mate but can succeed with the help of the king and with a timely sacrifice divert the opposing king away from the palace.
• A Queen-Guard with the help of a king can mate but cannot always pry the opposing king out of the palace.
• If ahead in pawns, it is best to try to exchange off the flying bombers since they can be a nuisance in the endgame.

Last revised by H. G. Muller.