John Smith wrote on Sat, Jan 3, 2009 03:04 AM EST:
How about having two pieces in the Dervish's place and its mirror:
Ninja - Moves as Alibaba but captures as Commoner. Promotes to Chain, which moves without capturing as a Queen, but relays the move of any piece it 'defends' to another piece it 'defends'.
Lion - Moves as Commoner but captures as Alibaba. Promotes to Flip, which moves without capturing as a Queen, but makes the pieces a Queen's move away's non-capturing moves capturing, and their capturing moves non-capturing.
These pieces are in the spirit of the Dervish, I think.