I'm a new player, and in card games I usually like playing a defensive deck. Who has the best defensive deck, the kind that doesn't attack but forces your enemy to try to get through your forces to do anything?

I don't think those type of decks work particularly well in this game... maybe a Tully Riverrun deck or a Bara Shadows deck with Queen of Thorns.

Skowza said:

Skowza is right; but it depends on what you mean by defensive. Tully defense is also the first thing that sprang to my mind.

Depending on what you mean by defensive, Martell might be what you're looking for. A lot of Martell (the Vengeful keyword in particular, but also cards like Taste for Blood and Areo Hotah) keys off of losing challenges. They also have a lot of cards, particularly events, that either negate challenges, blunt their effects, or make opponents pay for winning them (often by stripping icons off their characters).

Here is my favorite defensive deck: http://www.agotcards.org/deck/v/1597

Its GJ Wildlings, focus on Stealth and High STR. Have your opponent go first, and try to get through your Wildlings - then hit him with your kill locations if he fails. Fun times!

Mmmmm for defence I run a Tully-Kingsguard, with the agenda that gives you power for defending and having a KG in play. I prefer this over the locations (riverrun and the other one ¿winterfell?) because I find them to expensive. My estrategy is have only one KG (maybe two) in play any giving time.

Use the locations that blank attackers to avoid stealth and deadly. Gain power slowly but consistenly with some renown characters and defending. It has a lot of tullys but not all....cause it is not a 100% tully deck. I couldn't not put the peasants and the swords.

It's fun, not the best deck, but fun. It gets really good in a 3 way melee, with the opposed and support mechanic. The only thing that lacks is a decent attachment control...without using the maesters....