(25.06.2013) Here is the first original of Proca Retractor type published in the website. It is good presentation of the new fairy condition Circe X. The author is Paul Raican from Romania.

1.Kg5xPh6(Ph7, Bh7>g8)! g7xBh6(Bc1)+

2.Kf5xPg5(Pg7, Bg7>h6)! Bg8-h7+

3.Kf4-f5 g6-g5+ 4.Ke3-f4 d5-d4+

5.g7xRh8=B(Rh8, Bh8>g7) & 1.gxh8=Q(Rh8, Qh8>h1)#

Circe X: as a normal Circe - captured units (not Ks) reappear on their game-array squares, of the same colour (pieces), on the file of capture (pawns), or on the capture file’s promotion square (fairy pieces), but if the rebirth square is already occupied by another piece (A) it must immediately move (without capturing) vacating the square for landing of the captured piece (B). The capturing side decides where the piece A should move. If  there is not possible legal movement, the capture is not allowed (or possible variation – the captured piece disappearing).

Proca retractor: white retracts n moves to reach a position for a normal problem (usually a #1). White must retract a legal move, Black defends by retiring any move he wishes. If a capture is retracted, the capturer decides if and which piece was captured.