It's not exactly a half-machine, but here's my clockwork servitor template. Similar idea, just more campaign specific.
CLOCKWORK SERVITOR (Template)
Master Control, a horrible “informational” entity, has built terrible servitors for thousands of years and more. Most of them are the clockwork horrors, but even worse are the Clockwork Servitors- creatures it has modified with mechanical devices, controlling them from afar and using them to destroy whatever enemies are out of its initial reach.
A clockwork servitor appears much as it once did, but wires, tubes, metal plates and control crystals are set in it. The actual appearance of a clockwork servitor varies according to exactly which special qualities and special attacks it is gifted with.
Clockwork servitors do not speak, but rarely Master Control will speak through them.
CREATING A CLOCKWORK SERVITOR
“Clockwork servitor” is a template that can be added to any corporeal aberration, animal, beast, construct, dragon, fey, giant, humanoid, magical beast, monstrous humanoid, outsider, plant or shapechanger. The creature’s type changes to aberration. It uses all the base creature’s statistics except as noted hereafter.
AC: Increase natural armor by +5.
Attacks: If the creature does not already have a slam attack it gains one. The base damage for this slam is 1d8 for a medium size creature, scaling normally.
Special Attacks: A clockwork servitor retains all the base creature’s special attacks with the exception of spells granted by a deity or by nature, and is typically instilled with 1d4+1 of the following special attacks, all of which are exceptional abilities:
-Spinning Blades: The servitor has had a spinning blade attached to one arm or forelimb. This blade deals a base 1d12 hp of damage, with a threat range of 18-20 and a nonmagical enhancement bonus of +2 due to the quality of the material and construction.
-Range Finder: The servitor’s eyes have been replaced by strange crystalline devices, giving it a +4 (unnamed) bonus to ranged attack rolls.
-Flame Thrower: The servitor has a flame throwing device implanted in it. This allows a medium servitor to fire a 30’ cone of flame up to six times before needing to be recharged; damage is 3d10 for a medium creature, scaling with size (the tank can hold more fuel and burn it hotter in a larger creature) (Ref half, DC10+half HD+dex bonus). The cone’s length increases or decreases by 10’ per change in size category from medium.
-Electric Arc: The clockwork servitor can fire a line of electricity 5’ wide and 60’ long, dealing 6d8 damage (Ref half, DC10+half HD+dex bonus) as a standard action. A medium or smaller creature can do this once per day; increase this by one time per day for every increase in size category.
-Smasher: The clockwork servitor has either had one of its hands replaced by a large, hammer-like device or has had an additional limb grafted onto it. The smasher can be used to attempt to strike an object without drawing an attack of opportunity; it has a nonmagical enhancement bonus of +2 and deals 2d6 points of damage to inanimate objects, ignoring the first 8 points of hardness. (The smasher includes a sensor to aid in attacking the weakest point.) The smasher deals less damage to creatures (1d6) and the clockwork servitor will use it against them rarely as it likely has a better attack form.
-Slug Thrower: The servitor has a long tube built into it that can fire a burst of metal slugs as a ranged full attack action (range increment 120’), dealing 6d6 hp of damage. A clockwork servitor can fire ten bursts if medium size, increasing or decreasing by one burst per size change.
-Gas Generator: The clockwork servitor can expel a cloud of gas in a 20’ emanation. All creatures within must make a Fort save, DC10+half HD+con bonus, or suffer 1d6 points of temporary dexterity damage; secondary damage is another 1d6 points of dex damage.
Special Qualities: All clockwork servitors retain all their existing special qualities and gain the following:
-Construct Traits: The servitor is immune to ability damage and drain, mind-affecting effects, poison, sleep, paralysis and subdual damage. Unlike a true construct it is subject to death effects, critical hits, etc.
-Electrical Immunity: All clockwork servitors are immune to electrical effects.
-Hear Radio: Master Control retains control of the servitors through a mysterious nonmagical form of communication called “radio” that all servitors can hear, but which is generally inaudible to other creatures (with the exception of some constructs).
-Immunity to Bluff: A clockwork servitor cannot be bluffed by a living creature, as it has the ability to monitor the biofunctions of creatures around it.
Abilities: Adjust the base creature’s strength and dexterity by +6. Note that unlike a true construct a clockwork servitor retains its constitution score.
Skills: A clockwork servitor gains a +10 racial bonus to Climb, Jump, Listen, Search and Spot checks.
Feats: Clockwork servitors that qualify for them gain the following bonus feats: Cleave, Combat Reflexes, Expert Tactician, Fleet of Foot, Improved Bull Rush, Improved Initiative, Power Attack.
Challenge Rating: Adjust according to the base creature’s HD: up to 7, CR+3; HD 8 to 14, CR+2; HD15+, CR+1.
Alignment: A clockwork servitor is always Lawful Neutral.
Advancement: A clockwork servitor’s advancement comes only through the actions of Master Control, building more enhancements into it.
REMOVING THE TEMPLATE
Removing the clockwork servitor template magically requires a Limited Wish, Wish or Miracle spell. A Shatter spell cast on the crystal will also work, although the clockwork servitor may attempt a Fort save to avoid the effect. Alternately, if the controller crystal in the creature’s head or spine can be destroyed (hardness 8, hp 6; requires successful attack roll; the crystal has the character’s AC, +4 for size). Finally, a Disable Device check, DC 36, will allow for the disabling of a control crystal.
When the crystal is removed the clockwork servitor falls into a deep comatose sleep for 10d4 hours. All special attacks and qualities gained cease to function, though the grafts remain. The ex-servitor’s strength and dexterity drop to 3 points below their level as a clockwork servitor. An ex-servitor can take Hear Radio as a feat if desired the next time they are eligible for one. The ex-servitor loses all feats gained as a servitor.
Sucks about losing your mag, and though I understand the harsh reactions I tend to have a little more sympathy for ya.