Hearthpwn

I can see a good opening, but you have 20 self-damage and only 8 heals so could be sketchy.

How about replacing Ornery Tortoise with Corridor Creeper? There are no more good heal cards that are odd-costed.

I'd possibly suggest the 3 mana 2/4 that heals you for 3 at the end of the turn for a replacement 3 drop. 1/1 less stats but can get good heals. Or the 3 mana 2/5 that when has 3 or more attack gets lifesteal and taunt which you can activate with fungal.

I've considered Benevolent Djinn, the problem is that it doesn't work with Happy Ghoul. Paragon of Light might be better in this deck.

Ah true, of course it won't be able to combo with Happy Ghoul xD