So here’s the TLDR version:
- Use low casting cost spells and creatures with Battlecry or Charge
- Have some sort of wave clear
The long version:
Maexxnas strengths lie with her ability to maintain board of dominance. She starts the game with two 1/2 haunted spiders. Each one of the spiders has a deathrattle which creates two 1/1 spectral spiders. In addition, her hero power forces her to boomerang two of your minions back into your hand each turn. This ability makes it so that if any creature that you cast which does not give you an immediate benefit is completely useless as it will be back in your hand before you get a chance to use it. A special note here is that she will use the ability every single turn before she does anything else.
The best way to take her down is to use her hero power to your advantage. The main structure of your deck should be comprised of low casting cost creatures who have either Battlecry, Charge or a useful persistent ability. The best options are:
- Abusive Sargent, he is absolutely essential. He is going to help your minions take down larger creatures when you need to and help deal extra damage when you don’t.
- Elven archer, this isn’t a bad option but even if you have two Elven archer’s running at the same time you’re not going to be able to keep up with all the spiders unless you have something else to help you clear waves.
- Southsea Deckhand, a decent option as long as you know you’re going to have a weapon.
- Bluegill Warrior, two damage two Mana it doesn’t get much better than that.
- Ironbeak Owl, the first two games that I won against Maexxna occurred due to an Ironbeak Owl in my opening hand that silenced all of the Haunted Spiders.
- Dire Wolf Alpha and Timber Wolf, these are certainly good options to add a little bit extra damage but they are especially effective with Unleash the Hounds.
- Kobold Geomancer, extra spell damage pretty self explanatory.
- Novice Engineer, more cards are always better.
I don’t like Arcane Golem in this slot simply because you don’t want to see any Sea Giants until you absolutely have to. All an Arcane Golem will do is bring that time closer.
Wave clear options are pretty self explanatory. I put Consecration, Holy Nova, and Lightning Storm all in the same category. They are decent options as long as you have the spiders silenced. I put Explosive Trap in a little bit better category simply because you have full Mana to react to it the following turn. With the previous three you’re spending Mana on your own turn and the enemy still gets to attack you on her turn. With explosive trap you cast the spell, the enemy attacks and then all of her Haunted Spiders end up creating spectral spiders which cannot attack you that turn. On your next turn you have a full Mana pool to react.
Alexstrasza is the only legendary that I would absolutely recommend here. By the time you can cast Alexstrasza you will likely be at a very low health. Normally you would have to choose between boosting your own life to 15 or reducing the enemies life to 15. But since Maexxna will automatically bounce Alexstrasza back to your hand you can do both.
Furthermore you can achieve an absolute lock with Alexstrasza. If Maexxna has an entire board full of 1/2 or 1/1 spiders and she cannot cast any other minions she won’t have the damage to do all 15 in one round. If in your hand you have alexstrasza and either a Hound, a Stonetusk Boar or in Elven Archer you can cast Alexstrasza each turn which will keep your life always at 15 and you can cast one of those three cards which each will do one damage to her. It may take you 45 turns to kill her but eventually you will win.