These thick leather boots are lined with metal plates on the front, back, and on the soles. The underside of each sole contains two small jets, and when activated the device jets emit powerful blasts of fire, propelling an individual forward and increasing his running speed. Goblin rocket boots require an experimental substance called goblin rocket fuel. The boots have been known to malfunction and explode injuring the wearer and creatures around him.WoWRPG 215
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Goblin Rocket Boots are created by engineers who have specialized in Goblin engineering, and have a minimum skill of 225.
During patch 2.3.2 the boots were hotfixed to require an Engineering skill of 225 to use, though it does not appear in the patch notes. The boots do indeed explode, and on average, after only two or three goes. The explosion does no actual damage, but does knock you down, and leaves you with ruined boots, although some components can be recovered from the wreckage.
In general, a cost prohibitive way to escape from trouble, and the Gnomish Rocket Boots are generally considered a better choice as despite being slightly slower and requiring Engineering skill to wear, they don't get destroyed when they malfunction.
However, there are theories that the Goblin boot explosion can be avoided if the speed effect is cancelled before the 20 second span is reached in full. [1]
Still... a plan without Rocket Boots, is no plan at all...