Hearthstone: Grobbulus Heroic Guide for Priests

Grobbulus is the second boss in Curse of Naxxramas Construct Quarter and actually he is the most challenging encounter in this wing. Due to the nature of his hero power and the minions he plays, once again I found Priests to be the most suitable class to defeat him on heroic mode.

Grobbulus has 30 health on normal mode and his hero power is to deal 1 damage to all minions for 2 mana, if a minion dies from this hero power Grobbulus will automatically summon a 2/2 slime. On Heroic version, Grobbulus has 45 health and his hero power deals 2 damage to ENEMY characters including our hero only for 0 mana and if any minions die to this hero power he will summon 2/2 slimes. At least the stats of the slimes remain the same :D

Grobbulus also makes use of cards like Echoing Ooze and his encounter exclusive spell to buff his minions up. When Grobbulus uses Mutating Injection on Echoing Ooze, out of nowhere you will be facing x2 5/6 minions, which is quite insane to be honest.

Is there a better class in Hearthstone than Priest to deal with such mechanics? The class has answers to everything! 

Whenever you have to play a Priest against any boss in Naxxramas, the tactic will always be the same; use your spells like Inner Fire and Divine Shield to get huge minions and kill the boss. This of course requires a really good starting hand. If you don't get key cards on time, it will go downhill from that. 

Here is the Priest deck I used to defeat Grobbulus on Heroic difficulty.

Mulligan: Deathlord, Inner Fire and Divine Spirit form the ideal starting hand. The first Deathlord is mainly to stall the game though as there is a high chance that he will die by the time you buff him on turn 4. So you need to have another minion to fall back on.

Strategy: It's basically the same as all the other bosses. Play your minion with highest health and try to buff it up as much as you can. You can basically do this fight with only 1 or 2 minions at the most. It's all about staying alive until you are able to play that minion.

Grobbulus' board will get crowded, so Holy Nova is a great way to clear the board. Shadow Word Death will be the answer to any minion that is buffed with Mutating Injection. Healing priority will go to your buffed up minion unless you have less than 3 health in which case you will die to hero power, so you will have to heal yourself first. If you have another minion on board that will die to Grobbulus' hero power, it is also a better idea to trade that minion with one of Grobbulus' minions in order to avoid getting a 2/2 slime.

This fight might require some attempts before you are finally able to defeat him. It all comes down to your starting hand. If your hand is ideal, there is no real reason to lose against Grobbulus. Just don't make the mistake of running Nerubian Eggs. While it might sound logical at first, you will get overrun in no time.

This is how my board looked like when I had lethal. I basically had this 1 minion fully buffed almost the entire time. 

Good luck and have fun.

PS, Gluth and Thaddius heroic guides will be uploaded later.