The Steel Machine appears in the 9th Chapter of the Void Quest within the Midnight Channel. It greatly reduces damage from Physical, Elemental, and Almighty attacks while having normal resistance against Light and Dark. It will alternate between using Navas Nebula and physical attacks. If there are any attack items available, such as Firecrackers, they can be used to knock off most of Steel Machine's health since they do not suffer the damage reduction penalty. Elemental magatama items or Smart Bombs will kill it outright. Upon being defeated, it may drop the Tungsten material. Selling 4 Tungsten at Daidara will unlock the Great Sword weapon for the protagonist.
In Golden, it appears in Chapter 8 and 9 and may also be summoned by Supreme Hand. It may also drop Milky Quartz and Culurium for trade at Shiroku Pub.