This historic variant is one of the strangest that ever acquired large popularity: many strange pieces, a 'citadel' square as board appendix to provide an alternative winning condition, strange to very strange promotion rules. Perhaps a bit too much to capture that exactly in an Interactive Diagram, but what can be done is already useful enough to make it worth the effort.
Tamerlane Chess
This historic variant is one of the strangest that ever acquired large popularity: many strange pieces, a 'citadel' square as board appendix to provide an alternative winning condition, strange to very strange promotion rules. Perhaps a bit too much to capture that exactly in an Interactive Diagram, but what can be done is already useful enough to make it worth the effort.