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Summary
DescriptionWsb 525x511 phase3 3d.jpg
English: Additioanal Pieces are: Spider and Archbishop.
White has chosen to Gate his Spider and Archbishop respectively on b1 and h1 squares, whereas black has chosen to gate them on h8 and a8 squares. Gating sqaures cannot involve King and Rook at the same time (preventing from introducing both pieces at the same time when castling). Each piece must be gated in a different square (The additional pieces cannot wait to be gated on the same square, they cannot share a same square).
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