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Gnomish spider tank
Mechano-tanks, often called spider tanks, are mechanical tanks with a spider-like design. Making their first appearance in World of Warcraft, these tanks were designed by the gnomes of Gnomeregan to help defend their city and aid their allies. The leper gnomes, having taking control parts of the city, after Gnomeregan was irradiated by Mekgineer Thermaplugg, now pilot the ones left behind. The tanks are often either equipped with machine guns or a flame thrower, they are also capable of jumping great heights.
When they first appeared in-game, the model used came with a leper gnome already in the pilot's seat.
The Wrath of the Lich King expansion introduced a new model free of it's passenger, thus allowing the vehicle more use outside leper gnome populated areas.