I have some doubts about building a lannister deck, I already have the cards from the core.

I would like to know if is really necesary the lannister deluxe edition to get a good deck

or if it is more convenient to buy chapters?

sorry my english

and thanks!

You really need lannister deluxe(LOTR), this expansion have many good cards, especially Cercei Lannister. Chapters can make your deck much more powerful, but for start, I think, u can build strong deck from core + lotr.
We are playing agot for 2 months, and i decided to buy one chapter deck every month.

P.S Sorry for my english

you will need to have an additional copy of the lannister cards from core to make your lannister deck stronger.

in particular, enemy informer, cersei attendant, lannister pays his debt, and i'm you writ small.