Sure enough, I won't be able to use the second deck in the first runthrough of the first scenario...but I can use it in the second one. If we even want to abuse the rules I could kill my first player and the rules tell you to restart over. I could essentially make characters until I get exactly the weakness that I want

Or you could just pick the one you want. It's a cooperative game, after all, and I'm pretty sure the above approach would have the same "Yeah, dude, we're not going to play with you any more" response from anyone unfortunate enough to be stuck playing with you as outright cheating would.

Is there some ambiguity? Yes. But when you consider the player count descriptions and the instructions for starter decks, it's pretty clear how it's supposed to work. If you want to torment the rules to fit your personal preference, that's up to you, but don't pretend it's some honest pursuit of rule integrity, and don't expect many people to think you're anything but a rules lawyer on a rampage.

I don't think the rulebook was talking about how to make a deck that you then let sit around. It's about how you make one just before playing.

I think this exactly right. The Rules Reference says "During a campaign, players build a deck before playing the first scenario." A deck is intended to be for a campaign run. We don't know for sure how decks might transition from one campaign to another (I'm guessing they don't) but it looks to me like you'd redraw a new basic weakness even for the same deck starting a new campaign.

I don't think the rulebook was talking about how to make a deck that you then let sit around. It's about how you make one just before playing.

I think this exactly right. The Rules Reference says "During a campaign, players build a deck before playing the first scenario." A deck is intended to be for a campaign run. We don't know for sure how decks might transition from one campaign to another (I'm guessing they don't) but it looks to me like you'd redraw a new basic weakness even for the same deck starting a new campaign.

They do say a bit about transitioning at the end of the campaign book.

it states that you can continue to use your investigators in the next campaign if you want an extra challenge (as investigators will likely be damaged in most campaigns and those would carry over), but the typical intent is to allow new decks between campaigns.

We only have the one campaign so I do not know how often investigators will make it through well enough that you'd want to continue using them (other than to have a challenge), but the campaign guide said you can feel free to do either.

Sure enough, I won't be able to use the second deck in the first runthrough of the first scenario...but I can use it in the second one. If we even want to abuse the rules I could kill my first player and the rules tell you to restart over. I could essentially make characters until I get exactly the weakness that I want

Now, I have no idea what you're trying to say here. On your second playthrough of the campaign, you're using completely new decks. Why would the weaknesses you used in the first playthrough be physically unavailable? This isn't Arkham Legacy ; the rules never have you physically destroy your cards.

And where are you getting this rule about restarting if the first player dies? If everybody gets defeated, you go with the "no resolution" ending and proceed to the next scenario. If everyone outright dies (or irrevocably goes mad), you build fresh investigators with 0 xp and take them into the next scenario.

Also it is possible that every player has their own Gaming box. So They draw each from their own weaknes card pool.

It is Also possible that each player use only one common game set, so They draw from the same weaknes pool.

So in practice those two different cases use different rule to the basic weaknes rule, depending on if They have own core Box or not. Both plaing options Are completely valid! In Lotr Lcg Also it is possible the players build decks by using their own card pool, or that one player provide the common card pool to each player.

It would not hurt if this will be cowered in the faq.

In the case of Arkham Horror Lcg it is just fine if players have common or individual basic weaknes pool, because They can Also have individual or common pool for player cards, just like in Lotr Lcg.

Otherwice it would not be possible to player to change the Gaming croup between the games. When player plays scenarios 1-2 is Houston and goes to trip to NY and players there scenarios 3-6 and the comes back to Houston to play the game with another croup in the Local Gaming store. It means that in that case every player has to have their own weaknes card pool in anyway.

If the croup playes always in with the same players, the common weaknes pool is just fine option.