Very easy and fun; but the online client has some of the worst customization options I've seen. It does give you competitively viable decks for free, with some exceptions in card choice, which in spite of that minor complaint is a huge boon in this game's favor. However crafting the cards you need if you don't have them can be a nightmare given the extremely slow rate with which you get the crafting currency, incentivizing you to purchase the code cards to get enough duplicates to begin receiving the aforementioned currency.