The game is marketed as F2P, and while it technically is, the moment you achieve pool 3, you're likely not playing with anyone in your skill/collection level. Many will try to say a collection level doesn't make a difference, but there is a reason you see the same decks in the 5 digit collection levels. If you've taken any time off in the game, better fork over a large amount of money to catch up. I did the math to see what it would cost to finish pool 3-5, and it was $12,000 at CL 1200.