The incap card is put on top and the cards underneath it. It isn't a deck anymore and are cards under another card. The only reason deck is listed in my mind is because we are taking cards from Captain Cosmic's deck and it is all cards in his hero deck. Outside of stuff like End of Days I don't see any other powers or card plays impacting it much like cards under the Shrine of the Ennead.
The Ennead and The Shrine are not a Deck.
Cards under other cards usually have no text, or any other designators other than belonging to a particular hero/villain/environment. We know that the cards under Captain Cosmic's incap do not have the Construct keyword yet because they are refered to as "cards". I believe that once placed under Captain Cosmic they are no longer a deck, any more than cards under Savage Mana are a deck.
As I've pointed out before, his incap text directly refers to these cards as a deck when it is newly formed after incapacitation. Also, no one is calling the Ennead/Shrine a deck, I'm not sure why this is still brought up.
I never said what was under Shrine of the Ennead was a deck or specified as a deck I'm just referencing it as an item that is similar.
That’s not true. Well, it’s sort of true. Cards under other cards can be interacted with just fine. The only problem is that there are only a few cards that can interact with them, and End of Days and Into the Stratosphere don’t do anything to indestructible character cards. But it’s not the fact that they are under the shrine that prevents the interaction.
Fair enough I'm just looking at a similar instance where cards are played from under another card. Now Captain Cosmic's cards are not listed as being indestructible so I foresee End of Days being pretty bad for this Incapped hero.
Well, End of Days won’t be exactly good for him, but I’d say that the cards under him aren’t in play (because they’re a deck) so it won’t get rid of any constructs he hasn’t played yet.
Cards under Savage Mana and La Capitan can be destroyed by End of Days. It is that situation is likely why cards under the Shrine of the Ennead are specified as indestructible. The only reason I think deck is specified is because it is complied from cards in a hero deck but once they go under him it' should be no different than what is under Savage Mana, La Capitan, or Self Destruct Sequence.
No, because decks aren’t in play. Otherwise End of Days would destroy all the decks, and everyone would have to reshuffle immediately.
These are cards under another card not really a deck anymore once they go under his incap character card.
Why not? Why does puting them under another card make then no longer a deck?
Sounds like there's a set of views we probably can't reconcile without an official response.
- The cards under Captain Cosmic are a pile of cards that don't act like a deck (in that they can't be effected by things that play the top card, etc.) but also don't act like cards in play (can't be affected by End of Days)
- The cards under Captain Cosmic are a deck and treated as such in all ways
- The cards under Captain Cosmic are cards under another card and are treated as such in all ways (similar to cards under Savage Mana)
Does that sound like it represents the situation/views?
All the reasonable ones at least. I personally support the idea that all cards under character cards become character cards in a seperategame that happens in a parallel universe.
You can still call it a deck but I don't see anything from prior cases we have (of cards under other cards) or similar instances (like Shrine of the Ennead) that indicate it should behave like a hero, villain, or environment deck. Incap heroes don't have a deck and their cards are removed from the game. If it behaves like a hero deck then it should be suspectible to Fumbling Fool but then you have a question of whether you are discarding the hero card or the top card under Captain Cosmic. If it was the top card under Captain Cosmic then what do you do with this Contruct that now got discarded since there isn't a trash or deck it's associated with anymore?
Yep.
while this is true, in no prior cases are you instructed to form the cards into a deck before placing them under another card as is done here, so I don’t think that you can use their lack of deckness as a basis for comparison.
We will have agree to disagree until we ever see an official ruling as we are at a standstill on our viewpoints.
Agreed. 
Personally, I'm planning to treat it as a pile of cards that aren't a deck or cards in play (#1), as that's the one that makes the most sense to me given the intention. I honestly think the use of the word "deck" in the intro of the incap abilities was not intended to mean it is actually a deck, but until we get an official decision, we'll just have to go with our individual approachs on it. 
The first time I read the text for that power, I got briefly confused and thought that shuffling them into "a deck" meant to pick one of the decks remaining in the game and shuffle all the Constructs into that. Which of course makes no sense with anything in that text after the word "deck" (or the subsequently-available incap abilities), which is why I got confused :D.
Personally I agree with Rabit. I could be persuaded that 2 is correct, which would mean Experiment and the like could affect it but it does leave the question of how to handle discard effects. Which is why I think 1 is more likely.
I'm really not persuaded by 3 as it means Apocalypse or End of Days would mean Captain Cosmic would have no incap abilities at all to use which seems counter to the design philosophy of Sentinels regarding player elimination.