Well, the difficulty you face will depend largely on the tier you are playing at (bronze/silver/gold/diamond/champion)

Stay in Novice/Bronze for now, and decide how you want to play.

• If you want to get super competitive, you're going to have to spend a ton of money on cards, OR rent really good cards for a day or two when you want to make your push for each season (100x cheaper unless you plan to play a lot, for years - but no big upfront cost needed)
• Basically, unless the game collapses, the value of all the cards are going to keep going up - get the ones you like (or the ones that beat you a lot), and start stacking them, leveling them up, etc.
• Dailies as often as you can, and definitely use the quest potions, especially if you can afford to buy in bulk. They pay for themselves all the time, and WAY more much of the time.
• If you buy packs, I recommend using both the alchemy and legendary potions. You can see the math for different sets here.

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