The first thing you are going to want to do when logging into Hearthstone for the very first time is to complete all your basic sets. You do this by getting each of your nine heroes to level ten.
Now, you can play against other players, but with only the barest of essential cards, you will likely lose more than you will win. It will take you longer, playing other players, to collect the basic card sets for each hero.
The AI does not play Thrall in particularly bright ways.
Whereas playing the AI isn’t terribly exciting, it will let you learn the basic strategies behind each hero in a non-competitive environment. Even though the game tips state that you will earn more XP playing against other players, the experience you earn playing against the AI in your first ten levels is not insubstantial. For example, if you win your very first match against an AI, you’ll earn a full two levels of experience immediately.
But, you might be wondering: is there a particular AI-controlled hero that is easier than the others?
There definitely is. Thrall. The shaman hero. For whatever reason, the AI does not play Thrall in particularly bright ways. He’ll throw windfury on minions and then kill them on their very first attack. He’ll attack minions when he should be going straight for your hero with damage. He throws down heals on himself too early in a match. He’ll transform weak minions into frogs.
It’s also quite easy, and of paramount importance, to keep his side of the board clean of minions. Fewer enemy minions means fewer fires to put out in later turns. Couple that with the Shaman’s generally weak hero power at this level of play, and you’re left with a hero with little offense and not much defense.
I win eight out of tens matches against Thrall, in practice mode, no matter what hero I am playing. Eight to ten games to reach level ten. Then move on to the next hero to begin collecting your next basic card set.
This early in the game there will be inherent balance issues between heroes. In practice mode, some heroes are going to be tougher than others. Thrall just happens to be the easiest to defeat, given a very limited deck. On the other hand, the AI of Garrosh the Warrior can be particularly tough, especially against Mages. Warriors can put tough minions into play early, and Mages, relying only on the basic card set, don’t have much to work with in trying to keep Garrosh’s board clean.
If you do want to minimize your time spent getting all of your heroes to level ten, then playing against AI Thrall is definitely the way to go. After you get the complete basic set for all your heroes, then you can start exploring the game more fully.