Introduction
Hearthstone’s Arena is a very different beast than constructed. Now that Standard has come into play, arena not only has different strategies, but a whole slew of different cards as well. Because of the nature of not knowing what you’ll be offered, the meta in arena differs highly than a meta in which you can construct a deck around certain tactics. Because of this, the best classes are very different from constructed. In arena a card’s value is not typically based on its synergy with your deck, but rather on its own merit. That being said, crafting a deck that follows a decent mana curve is another very difficult task, and sometimes the less valuable card is better if it fills a hole in your deck’s curve. It is also worth noting that at the moment Whispers of the Old Gods has a higher impact because Blizzard weights the new cards higher, so they appear more often. Without further ado, let’s take a look at which class takes the title of best arena class, and which one simply doesn’t cut it.
The Best of the Best
For a long time Mage was considered the 
There are a lot of reasons that Mage climbed into its number one spot originally. It has the best board clear in the form of Flamestrike – a common. It also has the best face damage spells in the game – Frostbolt and Fireball, two more commons. They also have some of the best removal – the damage mentioned already, Flame Lance, Blizzard, Forbidden Torch, Dragon’s Breath, Arcane Blast, Forgotten Torch, and the mother of all removal, Polymorph. With an arsenal of such strong removal, and most of it common cards, is it any wonder that they took the top place? It is certainly worth noting that class cards also get a higher weighting than neutral cards, so these mostly common cards will all appear fairly often.
However, it doesn’t stop at their spells. Mages also have some of the best class minions in the game, in terms of value. Water Elemental is the original value minion, often trading into two or even three minions before dying itself. But with League of Explorers came an even more valuable minion – Ethereal Conjurer. This card has been the core of many value decks in constructed over the past months, in arena its value is easily enough to win the game alone, especially with multiple copies. Both of these incredible minions are commons, only adding to their power in arena.
Lastly, the Mage’s hero power is a large factor in its strength. Arguably the second best hero power after Warlock’s Life Tap, the Mage’s hero power is incredibly versatile. Most frequently it simply adds to the value that Mage is able to garner, pinging off low health minions and allowing far better trades throughout the game. However, it can easily finish off a low health opponent as well, as arena games can sometimes get into top deck wars where every point of damage matters. Overall it’s extremely versatile and generally useful.
The Worst of the Worst
To anyone who has played arena or watched arena streamers in the last year or so, the worst class is no surprise. Priest remains awful in arena, from day one until now. The only times it wasn’t worst was when Warriors took that slot, but they’ve received many good cards recently to make them decent. Priests remain at the bottom of the barrel, receiving almost nothing to help them over the last few expansions.
Their removal can be strong, but is almost always situational, and difficult to put into an arena deck. Shadow Word: Pain and Shadow Word: Death are both great, but putting either – Death especially – in a deck is a gamble that your opponent will give you value from them. While this is often a safe bet, the times where they get stuck in your hand can easily lose you the game. Shadow Word: Horror only compounds these problems. Entomb is a solid removal card, but it costs a lot and arena cards tend to be less valuable than constructed, so you’ll often lose value on whatever you take. Mind Control simply costs too much to be viable, especially in arena where fast decks rule.
Another reason they’ve retained their last place position is because of how many synergistic or just plain awful class cards they have. The Inner Fire + Divine Spirit combo is pretty neat in constructed, but when you can only get one piece they are simply two awful cards taking up places in your draft. Circle of Healing tends to only be good with Auchenai Soulpriest or Injured Blademaster – or a few other combos. The list goes on. The cards that are decent, like Holy Nova, are simply overcosted for what they do, especially when the healing is far worse without the synergies constructed provides.
The Whispers release actually managed to hurt Priest with its incredibly weak showing. Since C’Thun cards can’t be picked in arena, there are only two new commons and one of them – Power Word: Tentacles – is beyond garbage. Two other new spells, Shadow Word: Horror and Embrace the Shadows are equally bad. Shifting Shade is the only decent card they received for arena this time around, and they were already sitting at the bottom of the barrel.
The last issue is their hero power. They have the worst hero power for arena because it simply doesn’t interact with the board for the first few turns. If you don’t draw an early drop you can’t even attempt to salvage your being behind, and your opponents can easily snowball from turn one with simple 2/1s that you can’t easily deal with. Overall the class needs a lot of love if it’s going to make a comeback in arena any time soon.