One of the beauties of Amidol is the ability to vary the print color depending on the amount of KBR in the formula. Perhaps the coldest print I've ever seen was an Azo print developed in Amidol with Zero KBR. Of course, since the KBR acts as a restrainer, the image exhibited a touch of fog.
Hmmm, that gives me an idea for my notebook of Azo/Lodima using various developers. I need to mix up some amidol using BZ as the restrainer. I would expect some very cold prints, but let's see what actually develops.