Let's take a quick second to talk about quests in Hearthstone. Doing quests is the most effective way for most people to get gold to spend on Arena runs and card packs. Every day you get a new quest to do (up to a total of 3) and they can be worth 40, 60, or in rare cases, 100 gold.
Everyone knows this.
What some people don't know is that you can reroll a quest you are not interested in. I have mentioned it to many people and seen it mentioned many times on the internet, and inevitably tons of people are shocked and surprised about it. If you take a look at the picture I've included, you'll see that on your quest page each quest has a little red 'X' in the top right corner. A quick click or tap on that 'X' and you'll throw away the old quest and get a different one in its place.
The general strategy is to toss away any quest worth 40 gold that would take you ages to complete. A particular favorite throw away quest of mine is 'Only the Mighty,' where you are tasked with summoning 20 creatures that cost 5 mana or more. This could take quite a long time, as some games can be over before you even get to 5 mana anyway! You might also want to throw away 40 gold quests that want you to get wins with characters that you never play or don't have the cards to build an effective deck.
It's important to note that you can only reroll one quest per day, and it's not impossible to end up with a quest that you like even less. However, the ability to toss away a particularly difficult or time consuming quest and pick up something more to your liking is worth the risk and will ultimately net you more gold in the long run.
Stay tuned for my review of Curse of Naxxramas: Arachnid Quarter, which I'm quite enjoying and will be posting about in a day or two. Don't forget to log in and try the Arachnid Quarter out for free during the one month launch event!