Question : Lets say i play Wendy and on scenario 10, with all unique items removed from the game, what are the rules for replacement cards for her missing elder sign? Is everyone just making up stuff as they go for replacement cards, Is it just too bad so sad bye bye and she is out of luck, or is there a "replace this with that" system in place everyone is using?

Have you read the scenario card? It is right there, first thing under the special rules heading.

ahh oops, i confess i had not really read the cards, as i am just beginning league play. thanks.