hunchback
Member
Just use the codes, they don't go up in value or anything. If you want to spend money, the first (and probably only) thing you should buy is the Naxxramas adventure (all wings) which gives you single player content which gives you a bunch of very good cards that can only be unlocked this way.
Just do your daily quests to earn gold, and the optimal way to use gold is to spend them in the Arena mode. As long as you can get > 3 wins, you'll generally have a better return in terms of crafting dust + gold + pack compared to simply buying a card pack for 100 gold. Obviously you should watch Twitch streams or read guides on how to optimally play arena, but that's generally part of getting better at Hearthstone.
Very helpful info. Thank you very much.