I have found "sauce" to be a low quality version of other extract types. It's basically cheap terpenes taken from other plant sources, mixed with whatever source of cannabinoids you use, such as BHO, budder, shatter that didn't turn out well, etc. Tends to be high in flavour, but not in a natural way. And it tends to be low in cannabinoids, often with a lot of extra waxes. You see more and more "sauce" as the industry becomes more recreational and commercialized, but that's not necessarily a good thing. This is the kind of thing they make a wild sounding name for, slap it in too much packaging, and overcharge for.