An Iyzmiskan scientist who has dedicated his life to becoming one of the foremost experts on the phuzo ability of "frankensteining" -- in large part by experimenting on himself. He has worked with many of the brightest minds in Praque on an enormous number of experiments, and remembers each one with perfect clarity. He has a mind that doesn't forget anything, and a zealous passion for his craft.

Isidorius is not a reknowned figure, but he is a known one. Some people view him with scientific curiosity, others with disgust, and still others have had the dubious honor of working with him directly. He is self-absorbed and motivated only by those things that relate to the singular subject he is interested in; when his interest dries up, he leaves the project he was working on and never looks back. He is not popular, and even those who call him a friend don't always know what is going on in his head.

His extensive experimentation on himself has given him the genetics and abilities of a mutt, which is an endlessly fascinating idea to him. How many people does one have to combine to create a mutt? Can it happen if there are no mutts in the sample pool? He hasn't yet found anyone willing to fund a laboratory for such experiments, but he will keep searching.