The art looks sweet. Too bad I won't get too see it played against me ever.
Golden version must look amazing.
The problem is
(1) if you mulligan into it, it's a boulderfist ogre, which is definitely underappreciated, and has a lot of board presence, but most would prefer to have elven archer early on over it.
(2) if you draw into it MOST of the time, you will have a clear board.
If you get into the third case of actually having a board, this card is amazing especially since it sets up a battle rage for you. This is highly unlikely though. Definitely a pleasant surprise if it does happen though.
This is no flame leviathan, because it doesn't affect your opponent's board state, which is the main reason flame leviathan is ever played.
Now that I think of it more, I always wanted another 6 mana 6/7, boulderfist was the only card with such stats. People really undervalue the body of 6/7. It's playable, it's just not going to win by its presence alone. If you replace Highmane with Boulderfist ogre, MOST of the time, it's marginal noticable difference. This can be played in midrange warrior, it's definitely a very real midrange threat, much like boulderfist ogre. It's just not meta-breaking by itself.
But all of this is irrelevant, the card probably has my favourite art of all cards in hearthstone.
Clearly needs to be played with Grim Patron and Battle Rage. Might also give you an extra draw on an Acolyte of Pain. Looks fun. Is there a card you wouldn't want to get hit for 1 in patron warrior, actually ?
I've always liked the Flame Leviathan mechanic ; it's quite a surprise effect. I'd like to see this played.
The problem is that it will trigger most of the time at the beginning of your turn, but you want to enrage Grom right after you play it and most of the time you have already won when you have a patron board that survived a turn.