Des having multiple {Deceiver of Form} in play allow me to have multiple chances to flip something big and scary?
Well it's multiple cards and therefore multiple triggers, so I would assume that you would reveal the top card x times where x is the number of {Deceiver of Form} you control.
Yea just like {delver of secrets}. Don't see what you like on the first one, crack your {misty rainforest} and find something else on top for the 2nd delver, or deceiver...
Yep, that's legit. Deceiver allows you to put it on the bottom, even if they'd copy it. So you could sift through four cards that way (if you have four copies)