[quote=Flamelord]
Ironically, that means that technically a Sarcophagus makes your aura more black the more times you use it, since extended usage induced paranoid schizophrenia, megalomania, and delusions of grandeur, among other things.
[/quote]

As far as I can tell, Goa'uld are pretty inherently Black/Blue by nature. Parasitism, mind control, advanced technology and whatnot.