Can I drop a Newly Made Lord into play and have his effect go off with this plot?

No. Newly Made Lord's ability kicks off when it it played, Called to Court puts a card into play. Those are different things, and putting a card into play does not count as having played them.

Erwo! Glad to see you back! and no you can't. When a card says "after you play from hand" that is specifically referring to paying gold during the marshalling phase for it. Called to Court is a "put into play effect" that does not trigger "played from hand" effects.

Thanks! I'm actually coming to Gencon finally! I thought this was the case. It was the wording was so close with the from your hand stuff that I thought I would see what everyone else thought.

Erwo the Elder said:

Well, if I wasn't sure it was worth the trip, it certainly is now. Time to plan on cobbling a trip together at the last minute, per my SOP.

I am glad this came up. I was thinking about using this plot to do Enemy Informer shenanigans and get a kneel out of it.

You would get the Enemy Informer shenanigans! It is a response to coming into play.

Erwo the Elder said:

Now, Ser Arys Oakheart on the other hand….

Erwo the Elder said:

No sir it is not. Enemy Informer's response is to them being "played". Which means you must pay gold and "play" them from your hand during the marshaling phase.

Coming into play basically covers all ways a card enters play from an out of play state.

ktom said:

To pre-emptively expand on this, Ser Arys uses the words "After Ser Aerys Oakheart comes into play" and that includes both when he is played (pay his gold cost during your time as active player in Marshalling) and "put into play" (something like Called to Court). "Enters play" also works as a superset of both, in the case of characters like _The Viper's Bannermen_ and _Thunder Cavalry_. So the Cavalry will discard all those weenies whether you pay for him in Marshalling, or by putting him into play with _Ambush from the Plains_.