The Lords
The Lords collectively describe those demons with comprehensible goals and motives, reveling in chaos and corruption. They fight an unending battle against the natural order of the universe, invariable patterns coalece and form orderly systems and it is the sworn duty of the Lords of Chaos to unmake these systems and unravel these patterns.
Some worshipers form pacts with particular fiends, making personal relationships of mentorship and reverence. The truely pious support the overarching goals of chaos, adding the necessary entropy to break up stale and stadid systems. Finally, others seek to use the power offered by Chaos simply as a means to their own ends, without the pretense of worship or veneration.
What they think of Other Pantheons
The Saints - "Every lord needs its sycophant, these serve as a fine example of service."
The Ancients - "You worship weird space tentacles? you silly child we've got all the tentacles you could want."
The Twins - "You'll consider the dichotomy of good and evil, but why not think about embracing the duality between worship and desecration?"
The Scales - "Behold my fearsome god of shadow who I command by waving my hand before this fire, fucking idiots."
The Sun - "Well It's certainly powerful and chaotic, I can see the appeal, have you noticed how to bleaches and destroys anything that stays in its sight too long?"
The Watcher - "You like to watch too huh?"