If I play Saruman ally and target the Wraith of Carn Dum, do I need to trigger its effect?

The question also applies to Banks of the Anduin, Forbidden Descent, Weather Hills, and Abandoned Camp.

I don't think so. It is "considered to be out of play" so it never technically "left play". This is similar to the "considered to be engaged" rules.

I figured as much, just wanted to make sure.

Hmm. I think in the spirit of Saruman's ability those effects wouldn't trigger, but I could see the other way as well since they are technically going from in play to out of play.

Hmm. I think in the spirit of Saruman's ability those effects wouldn't trigger, but I could see the other way as well since they are technically going from in play to out of play.

They aren't leaving play, though, which is what is required for the referenced cards to trigger. This is identical to "considered to be engaged". If we asked the developers and they said the effects WOULD trigger, then I cannot understand why it wouldn't reverse the rulings on "considered to be engaged".

Yes, enemies considered to be engaged never trigger engagement effects, and so enemies considered to be out of play ought not trigger leave-play effects.

I got an answer from Caleb to my sword-thain question in another thread where the question is quite similar.

To trigger "leave play"-events the card must phyiscally moved out of the game. A "considered as out of play" does not move the card, so no, you can not trigger its forced effect.