# Is this move valid in the rollerball chess variant?

Can the white King move a space to the right, into the original location of the black king? This would be disallowed in standard chess, as one cannot intentionally put themselves into check. However, in rollerball chess, moving the king into this square is supposed to end the game, giving white the win. Thanks in advance!

No it is not legal. Just like in normal chess the king cannot move into check, even if it would 'win' the game.

http://en.wikipedia.org/wiki/Rollerball_%28chess_variant%29

King: moves and captures exactly as in Orthochess to any adjacent square but never to a square where it can be captured. It is the only piece to have a symmetric move.

But the French rules only say:

Roi: avance et capture exactement comme le Roi orthodoxe.

The French version can be interpreted to mean the same thing as the English version, but can also be interpreted to allow the case of moving to the winning square even when that square is threatened.

Interestingly I found another inconsistency between the English and French rules:

End of the Game: There are 2 ways to win the game:

• Checkmate the opposite King, or,
• When the King reaches the starting square of the opposite King, but only if it has turned clockwise.

The second case of which differs from the French version:

La victoire s’obtient de l’une ou l’autre manière :

• par échec et mat du Roi adverse
• en étant le premier à accomplir un tour complet avec son Roi, en le ramenant sur sa case de départ

So in the French version you have to complete an entire circuit with your King and it is not explicitly stated that it be clockwise. An anticlockwise (semi-)circuit is certainly very difficult anyway, since your opponent's pieces are much stronger in that direction than your own, so there does not seem to be a pressing need to forbid it.

In conclusion I find that the French rules, but not the English, leave open the option of winning by moving to the finishing square even when that square is threatened. I do not see any pressing need within the game to decide one way or the other, so best discuss which house-rule you use at the start of the game.