Hello, today talking with my friends we have a doubt with pale chain, when i trigger its response i must show to my opponent the card (attach or character of cost 1) that i put into play or i can wait to show my card until my opponent decide if he cancel its response?

Yes. You have to identify the card as part of proving you have met the play restrictions of the effect. That happens as part of initiating the link's effect.

I guess it's the same with Ambush from the Plains or any effect that puts a card into play from a private area (one known to a player, but not the others).

Yes. It's like needing to show that it is Meera or Guardian Wolf that you are bringing out of Shadows before the cancel decision is made.

Dredging up this old thread. As the discussion relates to Ambush from the Plains: if I have one or more valid targets in my discard pile, need I idnetify which target I plan to choose -- be it one of the cards in the discard like or an unknown in my hand -- before the cancel decision is made? It seems to me the answer should be "no" because it is clear from me having at least one valod target in an open knowledge area (discard pile) that the effect can succeed.

My understanding here is that the "Hidden" vs "Non-hidden" state doesn't really matter; you still have to pick your character before the cancel is chosen.

My reasoning for this isn't particularly sound, but it's as follows: the FAQ does state that all targets have to be chosen before an effect can be cancelled (p19 "Choose targets (if applicable) and proceed to step two."). It seems like the intent is that all information that could be available to the person making the cancel be available, and that the choice of words "choose targets" is a proxy for "choose upon whom/what the effect will act" even where targets are not explicitly chosen by the effect (eg. Ambush from the plains).

However, by a strict reading of the rules, you're not wrong Vaapad: it doesn't seem to require that you divulge information provided you have a valid target for the effect in an "open" area - mostly because Ambush from the plains doesn't explicitly target anything.

if anyone attempts to use Ambush from the Plains and doesn't pick who they are going to use it on before the cancel opportunity, then I won't cancel it, but the effect won't resolve since they didn't pick anyone before Step 2. yea. that's it.

if anyone attempts to use Ambush from the Plains and doesn't pick who they are going to use it on before the cancel opportunity, then I won't cancel it, but the effect won't resolve since they didn't pick anyone before Step 2. yea. that's it.

That's Alex's point though: Ambush from the Plains technically doesn't "choose" anything, by it's wording. Hence the ambiguity.

You have to identify the card that will be put into play as part of verifying play restrictions during initiation. You are required, as part of initiation, to verify that the specific character you put into play meets all play restrictions in order to actually initiate the effect. Specific play restrictions cannot be checked/satisfied generally.

Essentially, this approach is trying to say, "We'll figure out how the play restrictions are ACTUALLY met during resolution." But the rules say that play restrictions must be met/determined during initiation. So since initiation requires you to show that play restrictions ARE met, not that they WILL BE met by the time resolution is over, you have to indicate the actual character that will be put into play by the effect as part of initiation -- which means that knowledge is available before any cancel is played.