For those interested in history, the move of the Champion of Arciscacchiere invented by Piacenza is clearly only crossing empty squares when "travelling" two squares as Rook or Bishop (p118).
So, the Centurion cannot leap occupied squares as Alfil or Dabbaba. Piacenza insisted on this point several times in his description. (ex p119,p123). In Betza notation it is NnAnD. The Centurion is not a Squirrel.
However, Murray did not understand correctly and described the Centurion as a jumper in the eight directions. Pritchard repeated that definition given by the English historian and added the Knight’s leap that Murray had forgotten. He had forgotten it because Piacenza explains to have added the move of the Knight only few pages later. (The presentation of the rules by Piacenza is a bit messy).
So few pages later (p120), Piacenza confessed to have spoken with a certain Mr. Fantone which would have allowed him to have seen a chess book in which a Centaur also had the Knight’s power. Piacenza decided to adapt this idea in order to allow his new piece to reach any square on the board (otherwise the Centurion would have been color-bound and limited to half the board).
So, Piacenza’s Centurion jumps when moving like a Knight but does not leap on the rows, columns and diagonals.
In my opinion, the CVP would be inspired to give the genuine rules and not the wrong ones.
Piacenza's book is findable on the Internet. I can provide the photographs of those pages if someone is interested.
Last word for HG: there is nothing about a specific en-passant rule in that description of Arciscacchiere by Piacenza. So your implementation is not incorrect in my opinion. The description of this variant being at the end of Piacenza's technical book about chess, it is possible that this peculiar restriction was given for the orthodox chess that was presented by Piacenza. Then, someone would have extrapolated to the large chess variant as well. Again, we are not obliged to follow this as it is not written.
For those interested in history, the move of the Champion of Arciscacchiere invented by Piacenza is clearly only crossing empty squares when "travelling" two squares as Rook or Bishop (p118). So, the Centurion cannot leap occupied squares as Alfil or Dabbaba. Piacenza insisted on this point several times in his description. (ex p119,p123). In Betza notation it is NnAnD. The Centurion is not a Squirrel.
However, Murray did not understand correctly and described the Centurion as a jumper in the eight directions. Pritchard repeated that definition given by the English historian and added the Knight’s leap that Murray had forgotten. He had forgotten it because Piacenza explains to have added the move of the Knight only few pages later. (The presentation of the rules by Piacenza is a bit messy).
So few pages later (p120), Piacenza confessed to have spoken with a certain Mr. Fantone which would have allowed him to have seen a chess book in which a Centaur also had the Knight’s power. Piacenza decided to adapt this idea in order to allow his new piece to reach any square on the board (otherwise the Centurion would have been color-bound and limited to half the board).
So, Piacenza’s Centurion jumps when moving like a Knight but does not leap on the rows, columns and diagonals.
In my opinion, the CVP would be inspired to give the genuine rules and not the wrong ones.
Piacenza's book is findable on the Internet. I can provide the photographs of those pages if someone is interested.
Last word for HG: there is nothing about a specific en-passant rule in that description of Arciscacchiere by Piacenza. So your implementation is not incorrect in my opinion. The description of this variant being at the end of Piacenza's technical book about chess, it is possible that this peculiar restriction was given for the orthodox chess that was presented by Piacenza. Then, someone would have extrapolated to the large chess variant as well. Again, we are not obliged to follow this as it is not written.