I made a post recently lamenting my most recent cache containing M'Baku. Well, I recently put him in my kazoo/Patriot deck just to get some boosters. After the final cards revealed themselves I saw I lost and was getting ready to queue up a new game, when there was a flurry of motion on the screen and I saw the "Victory" logo. I hadn't realized that M'Baku had activated and went to just the right spot to make me win by a single point. I know that one instance doesn't suddenly make him a good card, but I found it ironic considering my recent post.
Mbaku is the one card I dream of being good.
I wonder if something like the buff to angel would make him somewhat viable, where he would come on the field even if he's in your hand.
I know that means you'd have less reason to actually play the card when you do have him, but at least his ability would have a better than 25% chance of activating.