As far as innovation goes, Blizzard hasn’t really done much when it comes to the Arena mode, and players can only wait for a new expansion in order to get a fresh Arena experience. There have been some changes made to the Arena, like the synergy-picks, which allowed some classes (we’re looking at you Mage) to get some really broken cards (the infamous Frost Lich Jaina) offered to them as synergy picks which made an already pretty powerful Arena class even more difficult to play against. But, the Dual Class event that arrived as a part of the Halloween celebration really hit the sweet spot, as players are having a lot of fun experimenting with the combination of two classes, and people that don’t like this idea only need to wait for this event to end.
You can say that this event just made some classes even more powerful than they were, but considering how many options you get when you combine certain classes, you can find something new and even more broken than the other player, and if you don’t like this idea you can just wait out the event and play Arena once it ends. The way the dual class Arena works is that you pick a hero and then you pick another hero’s hero power and then they get combined, which means that players get both of those heroes’ class cards as options when they draft their Arena decks.
This allows you to create endless possibilities, absurd combos, and terrifying strategies, and in all honesty, it’s just a super fun event that we hope comes back to Hearthstone again sometime in the future. Since the Ranked and Casual modes let you experiment with all kinds of cards, you can always find a weird deck that’s fun to play, but Arena plays a little different. There are certain cards that are a must pick if you want your deck to be solid. Well, you can pick whatever you want to, but don’t expect to get a lot of wins.
You can look at this Hearthstone Reddit thread to see what kinds of ideas the players have for Arena events, as some of them are really interesting, like the idea of drafting a 40 card deck and then discarding 10 cards once you finish, which was proposed by eucalculia. This is an idea that really promotes the deckbuilding part of Arena while decreasing the RNG amount which can sometimes just give you a lot of bad cards which end up ruining your deck.