A necromental is the undead remnant of an elemental creature. It retains only a fraction of the self-awareness that the elemental had in life, but it becomes twisted and evil.
This example uses a Large earth elemental as the base -creature.
Large Earth Necromental
Large Undead (Augmented Elemental, Earth, Extraplanar)
Hit Dice: 8d12 (52 hp)
Speed: 20 ft. (4 squares)
Armor Class: 20 (-1 size, -1 Dex, +12 natural), touch 8, flat-footed 20
Base Attack/Grapple: +6/+17
Attack: Slam +12 melee (2d8+7 plus energy drain)
Full Attack: 2 slams +12 melee (2d8+7 plus energy drain)
Space/Reach: 10 ft./10 ft.
Special Attacks: Create spawn, earth mastery, energy drain, push
Special Qualities: Damage reduction 5/--, darkvision 60 ft., earth glide, elemental traits, fast healing 3, undead traits
Saves: Fort +8, Ref +1, Will +2
Abilities: Str 25, Dex 8, Con --, Int 1, Wis 10, Cha 1
Skills: Listen +6, Spot +5
Feats: Cleave, Great Cleave, Great Fortitude, Power Attack
Environment: Elemental Plane of Earth
Challenge Rating: 6
Alignment: Always neutral evil
Advancement: 9-15 HD (Tiny)
Level Adjustment: --
This walking pile of crumbling earth and stone radiates a palpable aura of death.
An earth necromental smashes into combat like a typical earth elemental, though with even more devastating results, thanks to its energy drain ability.
Create Spawn (Su): An elemental slain by a necromental's energy drain attack (see below) rises as a necromental 1d4 days after death.
Earth Glide (Ex): An earth necromental can glide through stone, dirt, or almost any other sort of earth except metal as easily as a fish swims through water. Its burrowing leaves behind no tunnel or hole, nor does it create any ripple or other signs of its presence. A move earth spell cast on an area containing a burrowing earth necromental flings the creature back 30 feet, stunning it for 1 round unless it makes a DC 15 Fortitude save.
Earth Mastery (Ex): An earth necromental gains a +1 bonus on attack rolls and damage rolls if both it and its foe are touching the ground. If an opponent is airborne or waterborne, the necromental takes a -4 penalty on attack rolls and damage rolls. (These modifiers are not already calculated into the statistics above.)
Elemental Traits: An earth necromental has immunity to poison, sleep effects, paralysis, and stunning. It is not subject to critical hits or flanking. It cannot be raised, reincarnated, or resurrected (though a limited wish, wish, miracle, or true resurrection spell can restore life).
Energy Drain (Su): Living creatures hit by an earth necromental's natural weapon attack gain one negative level. An earth necromental can use its energy drain ability once per round. The save to remove the negative level 24 hours later has a DC of 14. When an earth necromental bestows a negative level on a victim, it gains 5 temporary hit points (10 on a critical hit). These temporary hit points last for up to 1 hour.
Fast Healing (Ex): An earth necromental heals 3 points of damage each round as long as it has at least 1 hit point and is within 5 feet of earth, stone, or metal.
Push (Ex): An earth necromental can start a bull rush maneuver without provoking attacks of opportunity. The combat modifiers given in Earth Mastery, above, also apply to the necromental's opposed Strength checks.
Creating a Necromental
"Necromental" is an acquired template that can be added to any elemental (referred to hereafter as the base creature). A necromental uses all the base creature's statistics, attacks, and special abilities except as noted here.
Size and Type: The base creature's type changes to undead, and it gains the augmented subtype. It retains any other subtypes as well, except for alignment subtypes (such as good). Do not recalculate base attack bonus, saves, or skill points. Size is unchanged.
Hit Dice: Drop any Hit Dice from class levels (to a minimum of 1), and raise remaining Hit Dice to d12s.
Armor Class: The base creature's natural armor bonus improves by 2.
Special Attacks: A necromental retains all the special attacks of the base creature and gains those described below.
Create Spawn (Su): An elemental slain by a necromental's energy drain attack rises as a necromental 1d4 days after death.
Energy Drain (Su): Living creatures hit by a necromental's natural weapon attack gain one negative level. A necromental can use its energy drain ability once per round, regardless of the number of natural weapon attacks the necromental possesses. The save DC to remove the negative level 24 hours later is 10 + 1/2 the necromental's HD. When a necromental bestows a negative level on a victim, it gains 5 temporary hit points (10 on a critical hit). These temporary hit points last for up to 1 hour.
Special Qualities: A necromental retains all the special qualities of the base creature and gains the one described below.
Fast Healing (Ex): A necromental heals 3 points of damage each round as long as it has at least 1 hit point and is within 5 feet of some form of its element (air for necromentals with the air subtype; earth, stone, or metal for necromentals with the earth subtype; flame for necromentals with the fire subtype; or water for necromentals with the water subtype).
Abilities: A necromental has no Constitution score. Its Intelligence changes to 1, its Wisdom changes to 10, and its Charisma changes to 1.
Feats: A necromental gains Great Fortitude as a bonus feat.
Environment: Any, usually same as base creature.
Challenge Rating: Same as the base creature +1.
Alignment: Always neutral evil.
Advancement: Same as base creature (or -- if the base creature advances by character class).
Level Adjustment: --.