Black Horse

[Konrad Klar]

Carn Dûm's text still trumps this, like Bûrat's text trumps Bad Company, or Thrall of the Voice (during draft).

[Bandobras Took]

No, it doesn't.

Source.

"Do abilities (e.g. Witch-King, Khamul, They Ride Together, Black Horse, Uvatha) which allow the play of RW followers override Carn Dum, or is my most recent Bag End mission deck completely stuffed?"

These abilities do override Carn Dum, but since the Bag End mission is so slow, your deck is probably stuffed anyway.

[Konrad Klar]

... (e.g. Witch-King, Khamul, They Ride Together, Black Horse, Uvatha) ...

Now I wonder in which situations the requirement:

· Your Ringwraith is at a Darkhaven or he is at the Ringwraith follower's home site.

must be observed.

[Bandobras Took]

I would imagine when playing a RW Follower.

Carn Dum vs. all the cards listed is a case of card vs. card. Not card vs. rule.

Since Carn Dum is a darkhaven, playing RW followers there is perfectly in line with the rules; it's just that the ability to play RW followers has higher priority than Carn Dum's effect text.

[Konrad Klar]

I would imagine when playing a RW Follower.

(time to sleep this week for me)

[Konrad Klar]

Carn Dum vs. all the cards listed is a case of card vs. card. Not card vs. rule.

No. Actually this is Carn Dûm's text vs. general rules. Where (according to Rulings Digest #119) general rules win.
Except They Ride Together, a cards that allow to have/play a Ringwraith Follower do not say where to play them, so where to play a Ringwraith Follower is governed by general rules.

[Bandobras Took]

Excellent point.