Hearthpwn

I have no legendary cards (except the cards from Naxx) and so I have to use basic cards to kill the heroic bosses.

Gohtik was a very frustrating challenge for me. At the end I defeat him but it was very close (at the end I had 5 hp).

I have no cards to force him to draw cards. So my strategy was to survive until his deck is empty. To counter his very strong cards (like Abomination Unrelenting Rider and Unrelenting Warrior) I used Doomsayer behind a taunt minion. Killing his Ghouls and Abominations also killed my spectral minions. The most important thing was to heal myself until he lose all his stronger minions. I used Shadow Word: Death and Pain also for his Rider and for the Undertaker. 

My luck in the successful try was that he used two of his Corruption cards on my Doomsayer cards (when he cast this spell on a minion it will not be attacked by his units for this turn). Afterwards I was able to play my Mogu'shan Warden with double hp.

I used Thoughtsteal and Mind Vision with the intention to steal his stronger minions. But you can use everything you get in this fight.

I think I made it in the 15th try because of the necessary luck by drawing the right cards.