The Ironstrider is an advanced powerplant used by Adeptus Mechanicus walkers such as the Ironstrider Ballistarius and Sydonian Dragoon. The device was created by the Tech-Priest Aldebrac Vingh in early M33. It is a near perpetual motion engine and is said to violate the laws of thermodynamics. Once walking, the engine essentially powers itself. After Aldebrac's death, the technology to create these engines was lost. So it is that today walkers with Ironstrider Engines are never switched off, as the Mechanicum is fearful they may not turn back on again as its Machine Spirit fades.