The enemy Witch has the friendly pieces and pawns under a spell, making them incapable of attacking the enemy King. However, the bewitchment does not affect the friendly Witch and King. The only way that the spell can be broken is for the friendly Witch to sacrifice herself. Thus, when either of the Witches disappears, the spell is broken for all the pieces on the board. The Witch moves like a Rook and can make one step on the diagonal. The King cannot castle. The Pawn promotes to Queen and other pieces, but not to Witch. The goal is checkmate.
Since the King is immune against attack from the enemy pieces, except the Witch, it becomes a powerful attacking piece. It is necessary to take advantage of this opportunity, already early in the game. It creates a very unusual situation on the chess board. However, one must be prepared for the eventuality that the enemy Witch sacrifices herself, in which case the King becomes vulnerable to the enemy pieces. For instance, if the King is placed within the scope of an enemy piece, it allows the enemy Witch to capture a piece. It’s not possible to take back, since now the King is in check. Note that a Witch gan give mate to the King aided by any other piece. Since the spell is broken as soon as the Witch is captured, the earlier bewitched piece can capture back. Blockula (Blåkulla) is the gathering place of witches in Swedish folklore (cf. Wiki here).
Here, White has played ambitiously with the king. Now, he can capture the bishop on f8. Since Witches are still alive, he is immune against attack from rook and knight. This allows Black to capture the knight on c3. White cannot capture back, because then the spell is broken and the white king is under check. Instead, the king may attack the pawns on the kingside, gaining an advantage.
☛ You can download my free Blockula Chess program here (updated 2017-09-26), but you must own the software Zillions of Games to be able to run it (I recommend the download version).
☛ Don't miss my other chess variants.
© M. Winther, September 2017.