Prior to it being automatically mailed, players obtained this pet by opening their gift box item (that they received in the mail) and accepting the quest which required them to turn in the gift item to an NPC in exchange for a choice of three pet items, one of which was the Zergling Leash. The name of the gift box, NPC, and quest zone was different depending on the player's chosen race.
- Former quest givers
- Merissa Stilwell at Goldshire for humans.
- Yori Crackhelm at Kharanos for dwarves and gnomes.
- Orenthil Whisperwind at Dolanaar for night elves.
- Jaeleil at Azure Watch for draenei.
- Magga in the Razor Hill for orcs and trolls.
- Vorn Skyseer at Bloodhoof Village for tauren.
- Claire Willower at Brill for undead.
- Marsilla Dawnstar at the Falconwing Square for blood elves.
Mini Diablo is inspired by the title villain of Blizzard's Diablo series of games (the name is literal; it's a very tiny version of the Lord of Terror). As its idle animation, it will occasionally breathe fire.