Adding new investigator cards to your deck

[BBB02112022 0]

I am wondering how people are handling upgrading their cards as new mythos decks come out.  Do you wait to use the cards in a particular mythos deck until you are actually ready to play the scenario they come with, or are you adding them when you buy them.  Due to my play group meeting infrequently, we are three scenarios behind right now in the Dunwich campaign.  But looking at the new investigator cards, there are ones I would like to try now.  Don't see that there is a hard fast rule for this, I was just wondering how others are introducing their new cards into their decks.

[Whipporwill 15]

They are part of the general card pool. If you have them available why wait to use them? There is nothing thematically or mechanically that says "no you must wait until Blood on the Altar to use Streetwise". If you have them use them.

[BBB02112022 0]

Makes sense and that is how I have been playing.  I wasn't sure if thematically I was short changing my game experience  ie. the investigators abilities unfold as the story unfolds instead of play 'em when you get 'em.  Thanks.

[awp832 447]

although technically each time you switch a 0 xp card in your deck it costs you 1 xp.   So if you were wanting to add 2 copies of Lone Wolf to your deck (blood on the Altar) then it would cost you 2 xp to do so,   doesn't matter the card didn't exist when you built your deck.   If it wasn't in there to begin with, it costs XP to acquire (unless you are using Adaptable).