With the introduction of this week's Battle of the Builds Tavern Brawl came something completely unexpected. In it, players are able to choose between one of four cards at the start of the game: Battlecry Bonus, Deathrattle Bonus, Murloc Bonus, or Spell Bonus. These remain as auras throughout the remainder of the match, providing their bonuses or buffs until either player wins. This marks a first for Hearthstone as the closest comparable card is probably Curse of Rafaam which remains active as long as it remains in the hand of your opponent. But what if this is Blizzard's way of testing out a new mechanic prior to the next expansion, which is due sometime in the next two months?

It wouldn't be the first occasion in which the Hearthstone team has used Tavern Brawls as a way of testing or previewing new mechanics. Captain Blackheart's Treasure was scheduled to debut a week before BlizzCon in what was supposed to be a sneak peek at the Discover keyword that was later revealed to be a part of the League of Explorers. Tavern Brawls have also brought us our first cooperative experience and active deckbuilding challenge. While the latter two haven't been implemented permanently in any way, it's safe to say that we'll be seeing their features used again in the future, particularly when it comes to adventures.

The process is relatively simple with such limited parameters at the moment. However, due to the way Hearthstone displays the play history, you're tasked with remembering exactly which aura the opponent chose. This is easy to do when there's only four different possibilities and you're reminded turn after turn which it is via buffs or minion spawns. Things would certainly be much more complicated depending on how the development team goes about the existence of auras as a whole.

In World of Warcraft they're predominantly utilized by Druids ( Empowered Tree of Life), Hunters ( Trueshot Aura), Paladins ( Aura Mastery), Shamans (with totems), and Warlocks ((Spell #140720)). That isn't to say other classes like Rogues and Priests don't provide auras via other methods like (Spell #113742) and (Spell #49868), respectively, but it wouldn't necessarily come as a surprise if the mechanic was limited to certain classes a la secrets. Given the fact that spells are exclusively class cards, we'd almost guarantee that Blizzard would also do the same with auras. After all, they fit perfectly into the lore of each hero, you wouldn't expect Gul'Dan to be giving off a neutral healing aura.

We'd imagine them to look something like this, similar to Overload: X except with the number of turns it lasts rather than how many mana crystals it locks.

Disclaimer: These cards were made by the Hearthhead staff and are not supposed to be balanced, they are simply examples.

Depending on how complex Blizzard wants to get with the mechanic, some can simply be consistent with others periodically activating. There's just a ton of awesome possibilities when it comes to this, but the ultimate question is as to how Hearthstone would need to change in order to accommodate the feature. For the sake of clarity and new players, we think they'll want a place to consistently display the effect, and that in and of itself comes with a wide variety of possibilities.

As per Battle of the Builds, it's obviously possible for each player have one consistent aura. This would likely remain the case if it were to be introduced in an expansion, but how do you handle multiple auras? Do they overlap? Does one effectively destroy the other? Are you forced to wait until one expires to play the next, therefore making each one a commitment? And again, this is assuming that auras expire and aren't simply permanent buffs.

And this mechanic isn't as daunting as you'd think. In essence we already have auras in the form of minions such as Raid Leader and Stormwind Champion. Yes, they're relatively simple effects, but these are basic cards that Blizzard expects casual players to understand and utilize. And in an age where Reddit users are complaining about weapons growing stale, this is the perfect chance to spice things up. There is a precedent in World of Warcraft with weapons like  Runeblade of Baron Rivendare which bestow an aura of movement speed and life regeneration. Imagine if you will, a weapon that gives bonuses as long as it's equipped, not just when it is being used.

Disclaimer: This card was made by the Hearthhead staff and is not supposed to be balanced, it is simply an example.

For now, we'll see how the community reacts to what is clearly an experiment, but the good news is that there's even more on the way. There are references to a Deal Your Fate brawl where the Tavern Keeper requires each player to discover random fates that affect you both.

What are Fates? Auras. Heck, Blizzard has already gone and named the keyword. Seems like it's just a matter of time to us.