Im going to buy GoT LCG. What's the difference between the 1st and 2nd edition? I am a 1st timer at LCG, so is 1st edition the one to buy?

Don't buy the 1st Edition. Soon, it and its entire card pool will rotate out of print.

The 2nd edition will have improved rules and layout, plus no huge back catalog to buy.

The core set will come out first, this September or October. It will have 240 cards, mostly single copies. You can put up to 3x copies of a card in a deck, so one or two additional core sets will be a good value.

Following this will be monthly $15 Chapter Packs, which are 60 card expansions (3x of twenty cards) in blocks of six packs.

In between Chapter Pack cycles are (presumably) $30 Deluxe Sets focusing on one or two factions in 165 cards. (3x of 55 cards).

There is no rarity--the contents of all sets in print is public knowledge and everyone has the same card pool available. The level playing field means nobody can "pay to win."

All in all it's an excellent model.

Also, the chapter pack cycles are on an approximately 3-4 year rotation cycle, so plenty of time to get your money's worth. Deluxe Sets and the Core Set will never go out of print as long as the game lasts--at least ten years, or so they say.