George Duke wrote on Wed, Dec 31, 2014 04:24 PM UTC:
Sure on all counts. I had to think for a moment whether Dragon can reach all squares. Though required 5-stepping, yes it can even on small 8x8. Not all middle-distance leapers, by contrast, reach every square such as Rector(4,5) unable to reach central four. It shows multi-path flexibility.
(http://www.chessvariants.org/large.dir/scorpionanddragon.html)
Well there can be alternative subvariants (mentioning it once and for the last time thank Muller for useful "subvariant" term) replacing King-accompanying Rook, as many subvariants as we want. The idea of Rook here would be comparable to Betza's Colourbound Clobberers having Carrera-Capablanca Centaur, though that Bishop-Knight is the one exception not being colourbound.