2. Fight a boss that casts "Living Bomb" on your pet
Unsummon your pet
3. Go to the Ironforge Auction House
4. Summon your pet
For those of you who have no idea whats going on.. The hunter class can tame a wild animal and turn it into a pet that fights alongside you. A spell cast by one of the enemies in the Molten Core turns your animal into a bomb. You can "unsummon" your pet, meaning it disappears until you want it back. If you then go to the Iron Forge auction house (a place where people go to bid on/sell items) and summon your pet, he explodes and kills everybody in the auction house. Under normal circumstances you can't do damage to people in the auction house.