|The subject of this article was removed from World of Warcraft in patch 4.0.3.|
When going through the Deadmines, there is a locked door before Ironclad Cove with a cannon pointed at it. If you don't have a rogue or engineer or a skeleton key, you can go into the small alcove you passed before arriving at the cannon and loot the gunpowder from a small Defias Gunpowder barrel. This allows you to fire the cannon which eliminates the door and spawns an elite patrol (which can take a group by surprise if not careful) to investigate the noise from beyond the door.
As an object Edit
The Defias Gunpowder is located in Deadmines.
Looting the gunpowder spawns a 17-18 elite that attacks the party member closest to the foundry.