We've had WoW and Diablo 3-themed BlizzCon/Worldwide Invitational in-game pets already, so you might say "hell, it's about time" when we tell you that Grunty, a murloc in Space Marine power armor, is on its way.
If I were a betting man, I'd say that all signs point to this being part of the BlizzCon goody bag as opposed to TCG loot, meaning there's even less of a chance for you to get it. Hope you're prepared to beat the queue to get one. Heck, I'm even considering trying to go after seeing this -- I can't wait to see the idle animations he gets. According to the screenshots, it looks like he even blasts the air with his flamethrower. For once, the fish will do the frying.
*puts on sunglasses, plays "Won't Get Fooled Again"*