Had this idea while in the shower.
Today's Cool Comic Book Moment on Brian Cronin's Are Comics Good? blog was Skurge the Executioner holding off the armies of Hel at Gjall while Thor, Balder, and some mortal warriors escaped back to Asgard (the mortals were originally being held captive in Hel). The moment is quite poignant and Skurge comes off as quite heroic since holding the bridge was certain death, even for a god like Skurge. I was thinking about a similar moment for my campaign.
The obvious, non-psychopathic enemy group would be the Fangs of the Wyrm. The Dragon King, Demitri von Rhinestadt, would be the only member whose word would be his bond as Groder worships the god of murder, Rath revels in mindless violence, and Marhault's entire modus operandi is based on lies and betrayal. I envisioned a scene wherein the party had to work with the Fangs to each group's mutual survival. Demitri vouches for the other Fangs when the party rightly questions whether they can be trusted, being devotees of murder, rage, and deceit. Demitri's rule of the Fangs is based on a combination of birthright and personal power; he vows that any Fang who breaks the truce would answer to him. This is far greater incentive than even personal survival.
This scene then brought to mind the various villain parties I had created. At first, I could only recall the Faces of Fear. Having started to write this, however, I recalled that Rath was a member of the Fangs and that the Fangs each have their own extensive entourages: Groder has his undead companions (the crazed skeleton and methodical zombie serial killers) and a virtual undead army; Demitri has his half-dragon sorcerer and dragon mount in addition to the troops he can levy and the awaiting demon army of his father, Ashardalon; Marhault has his devoted defender and traveling troupe (truly the weakest force of arms among the Fangs); and Rath has his Ravager companion and loyal followers among the Sons of Wrath cult.
I had always wanted a witch-type villainess on the Fangs and envisioned a pair of sisters, a siren and a harpy (in theme, if not in form). However, unlike the other members of the Fangs, these two never saw any development past that point. Tonight, I briefly thought about Saren filling in that roll but I feel her self-importance and particular philosophy do not fit particularly well with the Fangs. I can envision a manner in which she could fit, namely that she seeks to free those who would break the present order and expose true reality. Ashardalon could easily be the Face of Fear who speaks to her in her dreams and visions. But the crazy religious cult overtones of the Faces does not quite fit with the Satanic, overarching power of Demitri as head of the Fangs. And Saren's great insistence on self mutilation and grotesquerie is likewise incongruent with the Fangs' nobility and respectability. In Demitri's world order, there is a place for grotesque mutilation; it is in the dungeons and it is reserved for his enemies. No way would he defile himself in that way. So the Faces of Fear are not quite right to integrate into the Fangs.
But that still leaves the door open for them to work together. In particular, I imagined that Garrett would be encountered with the Fangs. The party would already know Garrett and the Faces, likewise the Fangs, and would wonder why he was working with the other group. In a just world, the party would be scared to death at the thought of these two groups cooperating. Their minds would boggle at the depths of evil they would seek together. I imagine Garrett is involved with the Fangs in one of two ways: either he is trying to infiltrate the group for some end (in which case he really tries to silence the party to protect himself) or he has taken leave of the Faces of Fear and has sought another powerful group to enable his cruelties (which would probably be my way of getting him more screen time when the Faces were geographically removed from the campaign, as the idea of Garrett is rather independent from the Faces).
God I miss D&D.