Half-Golem, Iron* (CR 4)

Medium Construct
Alignment: Same as character (if all Will saves succeed) or always neutral evil (if any Will save fails)
Initiative: -1 (Dex)
Languages: speaks whatever languages it spoke before its transformation

AC: 25 (-1 Dex, +11 natural, +3 masterwork studded leather armor, +1 masterwork small steel shield), touch 10, flat-footed 25
Hit Dice: 1d10+20 (25 hp); DR: 15/magic
Fort +4, Ref +0, Will +0
Speed: 30 ft. (cannot run)
Space: 5 ft. by 5 ft.
Base Attack +0; Grapple +8
Attack: Battleaxe +10 melee
Full Attack: Battleaxe +10 melee
Damage: Battleaxe 1d8+8/x3
Special Attacks/Actions: Breath weapon
Abilities: Str 27, Dex 10, Con -, Int 1, Wis 11, Cha 1
Special Qualities: Construct traits, magic immunity, rust vulnerability, (Ftr 1, half-orc)
Feats: Power Attack; Weapon Focus (battleaxe)
Skills: Climb +10 and Jump +10
Advancement: By character class (fighter)
Climate/Terrain: Any land and underground
Organization: Solitary pair, or squad (5-20)
Treasure/Possessions: Standard (the sample creatures all have masterwork studded leather armor, masterwork small steel shields and battleaxes)

Source: Monster Manual II

Example using a 1st-level half-orc fighter who has failed a Will save as the character, are provided here.

A half-golem looks like a bizarre and horrifying melding of a golem and the character it once was. The materials of its golem limbs twine and crawl across its flesh, like ivy growing across a building or tree. In many cases, a half-golem's flesh is horribly scarred and has the pale gray color of death. Half-golems speak whatever languages they spoke before their transformations, but their voices are harsh and strangled.

The limbs of an iron half-golem appear bolted or riveted to the flesh. Irregular and haphazard iron plates join flesh and metal limbs. The limbs can be fashioned in any manner, just like those of a stone half-golem, although they usually appear armored. They are much smoother than those of a stone half-golem.

Breath Weapon (Su): As a free action, an iron half-golem an emit a cloud of poisonous as from its limbs in a 10-foot cone directly in front of it. The cloud lasts 1 round, and the limbs emit another cloud every 1d4+1 rounds. The initial damage is 1d4 points of Constitution damage, and the secondary damage is death. A Fortitude save (DC 10+ 1/2 the iron half- golem's Hit Dice + the iron half-golem's Constitution modifier) negates both effects.

Rust Vulnerability (Ex): An iron half-golem is affected by rust attacks, such as that of a rust monster or a rusting grasp spell.