Back in Burning Crusade, my account was hacked. While Blizzard was working to restore my character, the GM said that there are a number of items that they couldn't give me back (like all of the cloth I had built up in order to craft that great warlock/shadow priest 3-piece set). To make it up to me, the GM gave me two Gift Vouchers after seeing that I seemed to collect pets. The vouchers could be used to get one of the original WoW collector's edition pets.
I immediately ran out, picked up the Panda Cub, and was trying to figure out what else to get when I noticed that I could not complete the second Voucher, because it was a quest and you can only do a quest once.
Fast forward to this week. I have since transferred my character over to the Horde. While I was on the beta server, I noticed that the name of the voucher had changed and that I could accept the quest (yes, I'm a hoarder and I've kept that thing in my bags for all of these years). I switched back over to live, and yes indeed, I could accept the quest.
So this is where I ask the pet battlers out there. If you had a choice between mini Diablo or the Zergling, which would you choose? I'm leaning towards Diablo just because I play more of it than Starcraft. But are either of these pets really playable for either PvP or for the Celestial Tournament?
TLDR: Diablo or Zergling - pick one (and why).