We have a little clue, the spoiler image cards of Celebrimbor' Secret:

You can see two words: ...., return a .... your hand.

What text do you think it could write?

My vote is:

Response: After Orophin leaves play, return a

card from your discard pile to your hand.

New suggestions....

And he has a keyword (it seems so, because there is too much margin top). I'd say: Ranged. (He can't be Centinel, he hasnt defense).

Well maybe it would be

Response: After orophin enters play, return a card from your discard pile to your hand.

It´s almost same as your idea, but slightly different.

My bet is that he is ranged and returns Silvan card from play to your hand when enters. Or from discard pile, probably when leaves.

return silvan ally from discard pile to hand

I've tested the text of several possibilities and the only one that fit was one where he brings a Silvan ally back from your discard pile when he enters play.

I've tested the text of several possibilities and the only one that fit was one where he brings a Silvan ally back from your discard pile when he enters play.

I hope that is it! It sounds fun and has some cool combo potential. That is the direction the game should take.

Honestly, when playtesting it, it didnt come in handy that often. You end up using an event to pull them into your hand way more often than you discard them. There are several different ways you can design Silvan decks, so you may end up chump blocking more with different deck designs and against certain quests.