Mechanatrix (CR 1/2)

Medium Outsider
Alignment: Usually lawful neutral
Initiative: -1 (Dex); Senses: Listen +4 and Spot +6

AC: 18 (-1 Dex, +6 banded mail, +2 large steel shield, +1 natural), touch 9, flat-footed 18
Hit Dice: 1d8+1 (5 hp)
Fort +5, Ref +1, Will +2
Speed: 20 ft.
Space: 5 ft./5 ft.
Base Attack +1; Grapple +1
Attack: Battleaxe +1 melee
Full Attack: Battleaxe +1 melee
Damage: Battleaxe 1d8
Special Attacks/Actions: Shockin grasp
Abilities: Str 10, Dex 8, Con 13, Int 13, Wis 10, Cha 9
Special Qualities: Cold resistance 5, electricity healing, fire resistance 5, outsider traits
Feats: Great Fortitude
Skills: Craft (any three) +5, Knowledge (any one) +5, Knowledge (architecture and engineering) +5, Listen +4, Profession (siege engineer) +9, Search +5, and Spot +6
Advancement: By character class
Climate/Terrain: Any land and underground
Organization: Solitary or team (2-4)
Treasure/Possessions: Standard

Source: Fiend Folio

Shocking Grasp (Sp): A mechanatrix can use shocking grasp once per day as cast by a sorcerer of 1st level or the mechanatrix's character level, whichever is higher.

Electricity Healing (Ex): Because of a mechanatrix's electricity affinity, any electricity attack directed at it cures 1 point of damage for each 3 points of damage it would otherwise deal. The mechanatrix gets no saving throw against electricity effects.

Skills: Mechanatrixes have a +2 racial bonus on Spot checks and a +4 racial bonus on Knowledge (architecture and engineering) checks.

Outsider Traits: Planetouched have darkvision (60-foot range), and they cannot be raised or resurrected (though a wish or miracle spell can restore life)

Despite their prowess, mechanatrixes prefer to avoid combat since they see it as destructive and wasteful. However, when they are forced to fight, they attack with shrewd tactics.

Mechanatrixes are not only immune to electricity, but they are actually healed by it. Because of this, they actively goad an opponent that uses any electricity attack.