This is according to my own experience. I have 257 arena wins and I like to keep stats. I searched previously but couldn't find an official source for this.
1st, 10th, 20th, 30th pick in Arena are always rare or higher: I call this Rare Turn, the others are normal turns.
At any normal turn, you can get one of these sets:
- 3 free
- 2 free 1 common
- 1 free 2 common
- (possibly 3 common as well didn't pay attention, can't verify this)
- 1 Rare turn ( % not sure I would guess about 5% - 10%)
In a normal turn roughly you have a 60% chance of getting a free and 40% chance of getting a common card.
At any rare turn, you can get one of these sets:
- 3 rare
- 3 epic
- 3 legendary
I got a legendary about every 10 games and since we have 4 rare+ picks I assume the chance of getting a legendary in a single rare turn is about 2%
I got an epic about every game so I assume the percentage for that is about 20%
TL;DR:
Normal Turn:
Rare Turn:
- Rare+ : 4 times
- Epic : 20%
- Legendary : 2%
I don't have a source for this its all according to my personal experience. These numbers are most likely wrong, but should give the general idea. More data is needed for better estimates.
In a normal arena deck you will have something like this:
- 15 Free
- 10 Common
- 4 Rare
- 1 Epic/Legendary
Of course if you are lucky you could get 4 legendaries, 10 rares, etc..
As of now, there has been no such announcement. As far as my memory reaches, the pack price has also not changed.
What has changed, though, is the Arena price. Originally (early closed beta), the Arena was called "The Forge" and required actual packs as an entrance fee instead of gold. In exchange, you would keep all the cards you drafted. And the rewards were also different. But since this was an early beta experiment, it's probably safe to assume they like it better the way it is now and won't change it again (especially since beta is over).
If we look at other big freemium games, we can see that there are frequently sales or special offers, but they usually affect real money prices only. So even if there will be such a sale or offer one day, it probably won't change the gold price, but instead alter the gold-to-money ratio.
Best Answer
You get up to 5 rewards on completing 12 wins or 3 losses. One reward will be a card pack. The other one to four rewards are random (dust, gold, single cards). More wins = more and better random rewards.
You always get your card pack. The worst random reward is "5 dusts". However, there is MMR matching in arena. You should expect to win at least one game on average even if you're terrible at picking cards.
There's two extremes of player here: Some players complete the dailies and log off, sometimes going for multiple dailies at once (3 or fewer games per day). On the other extreme, others play at least two hours or more each day (8 or more games per day).