|Art by Paul Harmon|
The Diaboli are a clade, a culture, or maybe a corporate entity that despoil worlds and corrupt other cultures—even whole universes—with faustian bargains of advanced technology and metaphysical knowledge. Maybe they've tempted some with miracle cures for disease or solutions for world hunger, but more often they appeal to baser instincts with advanced weapons of war or aids to the pursuit of pleasure. Whatever they offer, the cost is inevitably high--too high. The Diaboli are quick to sell fixes for the problems that arise, which inevitably just make things worse. At every turn, the Diaboli enhance their material wealth and create misery from which they are able siphon metaphysical energy. Some of their victims survive the devastation of their previous culture to become junior Diaboli themselves, and the toxic memeplex propagates like a multiversial pyramid scheme.
The Diaboli are very old; some believe they are the degenerate remnant of the Precursors who built the Ways. The truth, though, (at least as much as can be gleaned from a group as duplicitous as this one) is that the Diaboli fear the apotheosed Precursors. They believe the Precursors' Judgment is coming someday—and they plan to deny that judgment by becoming powerful enough fight back against gods. Only by draining or corrupting all potential rivals do they believe this end to be achievable. They view this as a net good for the entire multiverse and see themselves as defenders of order and civilization, albeit one where their inherently superior culture is in power.