Heroic Grobbulus - Priest's arcane deck
Consistency: Reliable (expected number of tries 1-3)
Grobbulus is one of those bosses, who gave Naxxaramas reputation of the most difficult adventure. And while I do not generally agree with it, Grobbulus is certainly a brutal boss. It is possible to create a good consistent deck for him, but you need a lot of PvE deckbuilding skill and experience to do it, since most of decks, that people created for Grobbulus are REALLY bad.
When players do not know what to do, they usually try to use Inner Fire priest - a cheap, but inconsistent archetype, which requires the perfect draw to win. And that's basically what 80% of Grobbulus decks suggest. In fact, there is almost no priest's Grobbulus decks without Inner Fire. It looks like people just can't think out of the box. So let's discuss what's wrong with Inner Fire and how to create a good reliable deck to defeat this boss.
So, why Inner Fire priest is bad?
Well, Inner Fire priest is a combo deck and as any combo it only works in mid- or late game. You just don't have enough mana to play the combo early even if you somehow managed to draw all combo pieces in time. It is super hard to create a buffed creature early, and it is even harder with guarantied 2 damage each turn. So you basically have to play your entire combo on the same turn.
However, most Inner Fire priest decks have no tools to survive until turns 8+ to play the combo, since targets for Divine Spirit/Inner Fire are generally bad for defence and decks always have several such minions. In fact, somehow with Inner Fire decks people usually don't plan for a long defence anyway, so a couple of buffed oozes leaves them no chances.
This deck works in a completely different way. It is basically a control deck, which is designed to keep the board clean and to wait for Grobbulus to run out of steam. Then it does a huge tempo swing with Arcane Giants, which will eventually kill the boss.
There are three distinctive phases you will have to play through:
Phase 1 (turns 1-4): This deck actually has pretty much no cheap defensive tools and you don't really need them. During these turns you are supposed to heal yourself with Power Word: Glory and Greater Healing Potions and use Shadow Visions to obtain healing or answers for phase 2. Grobbulus will mostly play cheap low-attack minions during this phase, so you can afford this.
Phase 2 (turns 5-8): By this time you must draw some AoE spells (especially Holy Nova or Excavated Evil for turn 5). This deck has a lot of them. You should use them for defence during these turns and you may need some silence effects too. This phase is the most important. Almost all loses happen during this phase.
Phase 3 (turns 9+): Now you can play Obsidian Statue and that's what you should do. When it dies, clone it with Eternal Servitude. By this time Grobbulus will run out of creatures. He will probably spend some spells on the first statue, but after this he will play topdeck game. So at this point you will be able to play your win condition - Arcane Giants preferably buffed with Divine Spirits. After this it will take just few turns to finish him off.
This deck has a lot of silence, healing and AoE - three things, which are vital for survival. Arcane Giants and Obsidian Statues (plus Eternal Servitude) provide powerful late game. Grobbulus has no hard removals, so he will have really hard time dealing with them.
Please note, that this deck has Divine Spirits, but no Inner Fire. You are supposed to use Divine Spirits on Arcane Giants, which can kill any enemy minion anyway. Face damage does not justify a dead card in your hand in a control-style deck.
Also keep Shadow Visions, which often will let you to obtain a card from the list above. By the way, it is one of the reasons, why I decided to don't use Explosive Sheep - you can't draw it with Shadow Visions.
Grobbulus has four Spectral Knights and they are quite difficult to deal with. Psychic Scream is the only AoE, which removes them right away, so sometimes you may want to wait a turn for additional minions before using it. Judge if you can afford it, depending on your health and resources. Also note, that silencing knights is generally useless. Your deck has no spells to use on them.
Keep silence effects for buffed oozes, if you don't have extra.
I had 80% win rate with it. Yeah. Believe it or not. This deck might easily be the best Grobbulus deck ever created. Well, I may be wrong, I didn't try them all of course, but those, which I tried (including my own previous version of this Grobbulus deck) weren't even close.
Blacktiger's Naxxaramas deck collection:
- Anub'Rekhan - Warrior's taunt deck Reliable (1-3 tries)
- Grand Widow Faerlina - Warlock's egg deck Reliable (1-3 tries)
- Maexxna - Priest's C'Thun deck Super (near 100% win rate)
- Noth the Plaguebringer - Mage's spell-only deck Super (near 100% win rate)
- Heigan the Unclean - Shaman's spell deck Reliable (1-3 tries)
- Loatheb - Priest's lifeforce deck Reliable (1-3 tries)
- Instructor Razuvious - Paladin's taunt deck Reliable (1-3 tries)
- Gothik the Harvester - Warlock's survival deck Reliable (1-3 tries)
- The Four Horsemen - Shaman's healing deck Super (near 100% win rate)
- Patchwerk - Mage's stunlock deck Super (near 100% win rate)
- Grobbulus - Priest's arcane deck Reliable (1-3 tries)
- Gluth - Paladin's bubble deck Reliable (1-3 tries)
- Thaddius - Rogue's betrayal deck Reliable (1-3 tries)
- Sapphiron - Mage's indirect spell deck Super (near 100% win rate)
- Kel'Thuzad (removed, since it is not good enough for my standards, to be replaced)
Provided win rates are approximate. They are based on my tests and so partially depend on how lucky/unlucky I was during my testing. Also keep in mind, that you need a bit of experience with a deck to use it to its full potential. So first attempts usually have lower win rates, than suggested in this list.