Ironwyrm golem

An ironwyrm golem was a golem built into the shape of a golem, holding a furnace, with the lifeforce of a dragon instead of an elemental.

Description
An ironwyrm golem trailed smoke from its nostrils because of the furnace in their bodies.

Abilities
Besides being able to attack with every part of its body, the drakestone golem had a breath weapon, the ability to spew flames of incredible power, comparable to that of an ancient red dragon. It was unaffected by any magic or magic-based ability other than those of cold and fire: the first slowing it down and the latter broke any ongoing slowdown, while healing it.

Combat
As a golem, they followed simple commands in battle. They however possessed enough awareness to know they could use their breath weapon on themselves both for healing and to break the effects of cold.

Construction
The ironwyrm golem's body called for at least of steel parts, masterful craftsmanship in either weapons or armor, and required the spells geas/quest, antimagic field, animate objects, incendiary cloud, and limited wish in its creation. A mage who could create one would almost certainly be able to use spells of any power, too.

Appearances

 * Novels
 * The Ruin