What does "Always" mean with regards to alignment descriptions?

[Blackrat]

Yes, this means that somewhere, in some backwater pub in Sigil, a LG pit fiend and a LG balor are planning a way to overthrow the Lower Planes.

Now that's a plot hook . I might have to use that if I ever run a planescape game.

 

[hamishspence]

WOTC sources

Expedition to the Demonweb Pits- stats out the Cambion- which is basically a 5/8 fiend (1/2 half-fiend, 1/2 tiefling)

and its "Often Chaotic Evil" and "Usually Evil" and "10% are Neutral or Good"

But its an Extraplanar Outsider with the Evil subtype- that is, a fiend!

So, by these rules, Evil subtype may not be an "overwhelming guarantee of utter Evilness" after all.

On "celestials who Fall become fiends" Again, not always true. Elder Evils- CE planetar servant of the obyrith Elder Evil Sertrous- retains planetar abilities, including the angel subtype and the Good subtype. Evidence that celestials, at least, can Fall and still be celestials.

WOTC site also has the infamous "succubus paladin" as the reverse- Good aligned fiend which retains Evil and Chaotic subtypes.