I would just like to create a casual deck for the two houses not represented in the core set that compares to the 4 houses included in the core set. Is there an expansion or chapter pack that does this?

comicthoughts said:

Deluxe expansions: Kings of the Sea and Princes of the Sun. Unfortunately in KotS you get 60 x 1 cards for outrageous price. One box of PotS contains 60 x 2 cards.

Princes of the Sun is easily enough to make you a decent casual Martell deck- I imagine at a competition it might not do well, but at home I find it one of the strongest.

Kings of the Sea is a different matter. 60 cards, including a plot deck and titles. That means that you'll only find 40 or so cards that actually belong in a Greyjoy deck. Against the core set decks, you could probably scrape together a 45-card ish affair that would be playable, but i can't imagine it doing very well, or being much fun for the player, without some kind of augmentation.

As for which expansions to get to make up the numbers on Greyjoy, that's probably a matter of taste. Every cycle of chapter packs will have several cards for each house, so it's just a case of pick and choose.