I'm going to try and write up how "I" put together my Arkham Horror decks.  I'll probably update this article in the future.  

I start by either choosing some general strategy I want to win by.  It could be a number of different things, here are a few I've built decks around.

• Bring Yog-Sothoth out for 2 or less power.
• Maximize the use of the Prize Pistol
• Force the player to lose by discard
• Make a deck of all mafia.
• I want to win with a single faction Syndicate deck (I know, sometimes I like a challenge)

The strategy isn't always easy to win by, but it isn't always about "how can I guarantee a win".  Sometimes I focus really hard on accomplishing some card combo, and even if I lost, I feel like I won with "style points".  

So anyway, I think about a strategy, then I think what faction or factions I want to work with.  Sometimes its obvious, other times not so much.  If we play with a lot of a certain faction, I tend to try and switch to another faction.  

Once I know what faction(s) I'm going to use, I go through each card in that faction and I sort it into three stacks of cards; My "Must Have" stack, my "Maybe" stack, and my "Not this time" stack.  

Now usually my "Must have" stack is still too large, so I have to go back through and parse it down a bit.   My goal here is about 35 cards.  Then I look through my chosen cards and I make sure my cards work together.  I also go once more through the cards I left out and see if any of them would make good combos with my "must have" cards.

At this point, I'm nearly done, so I go through my neutral cards.  I'm looking for certain things here, trying to plug in holes. Here are some problems I'm trying to solve with neutral cards, if my cards don't already solve it.

• Do I have at least one Day card to solve some nasty night card combo?
• Do I have either a conspiracy or two or a few good ways to kill characters; to deal with the Conspiracy Theorist?
• Do I have the means to deal with the Guardian Pillar?

Ok, so at this point, I should have some cool cards, and I don't have any obvious weaknesses.  Whats next?  Well, I need to make sure I can play cards every turn of the game.  You accomplish that generally by having a good ratio of low-cost characters to your deck size.  

Lets make some assumptions.

• You draw 8 cards, then either 1 card or 2 cards depending on whether you go first or not.
• First turn you most likely will have 3 domains, 1 with 2 resources, then 2 domains with 1 resource each.
• You're going to have a deck of no more than 50-55 cards, my math is going to assume 55.

Ok, you need a character with a cost no greater than 2 on your first turn.  Drawing 8 cards from the 55, you want around 8-10 cards with a cost of 2 or less to insure you can play someone first turn.  Trust me, when your opponent playing Hastur gets 2 successes on 3 different story cards with Magah birds because you don't have anyone to defend, you're going to wish you had more cheap characters!  

Because of this need for cheap characters, often at the very end, I end up looking through my "maybe" or even my "not this time" stacks and pulling in some cheap characters.  I keep pulling in, even if I need neutral characters or if I have to remove some of my more expensive cards, until I have 50-55 cards and 8-10 cheap character cards.

At this point, my deck should be pretty much done.  I then shuffle my deck, and I deal out a few hands of 8-9 cards.  I look for problems. 

• Do I have too many event or support cards?
• Can I play at least 1 card every turn?
• If I get the opportunity to select any 1 card from my deck, will I be able to choose a game changer, something "great"?

Ok, thats my thought processes on building a deck.  Currently I have several decks I wrote down because they were successful and I wanted to be able to rebuild them in the future.  In the future, I'll be building decks and writing down notes as I go through, so I can share these insights here in future articles.