Necronaut (CR 14)
AC: 25 (-1 Dex, -4 size, +20 natural), touch 5, flat-footed 25
Hit Dice: 32d12 plus 96 (304 hp); DR: 15/lawful or magic
Fort +10, Ref +9, Will +20
Speed: 50 ft.
Space: 20 ft./20 ft.
Base Attack +16; Grapple +43
Attack: Slam +22 melee
Full Attack: 4 slams +22 melee
Damage: Slam 4d6+20 (Includes adjustments for Power Attack feat)
Special Attacks/Actions: Assimilate corpse, trample 4d6+22
Abilities: Str 41, Dex 8, Con -, Int 7, Wis 14, Cha 16
Special Qualities: necromantic effects, SR 25, undead traits, unholy toughness
Feats: Alertness; Awesome Blow; Blind-fight; Cleave; Great Cleave; Improved Bull Rush; Improved Initiative; Improved Natural Attack (slam); Improved Overrun; Improved Sunder; Power Attack
Skills: Knowledge (the planes) +10, Listen +33, Spot +33, and Survival +2 (+4 other planes)
Advancement: 33-64 HD (Gargantuan); 65-96 HD (Colossal)
Climate/Terrain: Infinite Layers of the Abyss
Monster Manual III
Assimilate Corpse (Su): A necronaut can, as a move action, add the corpse of an opponent to its body. Once the corpse is added, the necronaut begins assimilating it. This process takes 1 round to run its course and heals some damage to the necronaut, based on the size of the assimilated creature: Small or smaller, 10 points healed; Medium, 30 points; Large, 60 points; Huge, 100 points; Gargantuan, 150 points; or Colossal, 210 points. Once a creature is fully assimilated, it cannot be raised from the dead. Before a creature is fully assimilated, an ally can pull it free with a DC 24 Strength check.
Necromantic Effects (Su): Necronauts are affected differently by some spells. Because each one is composed of bones and corpses, spells that create undead deal 1d4 points of damage per caster level to a necronaut, up to the maximum given here for each spell: animate dead, 10d4; create undead, 15d4; create greater undead, 20d4.
Trample (Ex): Reflex half DC 41 The save DC is Strength-based
Unholy Toughness (Ex): A necronaut gains a bonus to its hit points equal to its Charisma modifier x its Hit Dice.
A necronaut attacks by crushing as many opponents as it can beneath itself, then attacking any survivors with its slam attacks.
A necronaut's natural weapons, as well as any weapons it wields, are treated as chaotic-aligned and evil-aligned for the purpose of overcoming damage reduction.
A necronaut normally attacks using its Power Attack feat, taking a -5 penalty on its attack rolls and gaining a +5 bonus on damage rolls.
The necronaut is an undead monstrosity that abhors life. It communicates grudgingly with constructs and other undead, from whom others have learned what little is known about these macabre creatures. Necronauts are created by demons that on plains of bones in the Abyss and then sent forth to the Material Plane to kill, and to grow by adding bones and corpses to their hulking forms. Individual necronauts vary in shape but average about 20 feet tall, 20 feet wide, and 30 to 40 feet long; each one weighs some 50 tons.
A necronaut speaks Infernal and rarely bothers to learn other languages.
A subtype usually applied only to outsiders native to the chaotic-aligned Outer Planes. Most creatures that have this subtype also have chaotic alignments; however, if their alignments change they still retain the subtype. Any effect that depends on alignment affects a creature with this subtype as if the creature has a chaotic alignment, no matter what its alignment actually is. The creature also suffers effects according to its actual alignment. A creature with the chaotic subtype overcomes damage reduction as if its natural weapons and any weapons it wields were chaotic-aligned (see Damage Reduction).
A subtype usually applied only to outsiders native to the evil-aligned Outer Planes. Evil outsiders are also called fiends. Most creatures that have this subtype also have evil alignments; however, if their alignments change, they still retain the subtype. Any effect that depends on alignment affects a creature with this subtype as if the creature has an evil alignment, no matter what its alignment actually is. The creature also suffers effects according to its actual alignment. A creature with the evil subtype overcomes damage reduction as if its natural weapons and any weapons it wields were evil-aligned (see Damage Reduction).
A subtype applied to any creature when it is on a plane other than its native plane. A creature that travels the planes can gain or lose this subtype as it goes from plane to plane. This book assumes that encounters with creatures take place on the Material Plane, and every creature whose native plane is not the Material Plane has the extraplanar subtype (but would not have when on its home plane). An extraplanar creatures usually has a home plane mentioned in its description. These home planes are taken from the Great Wheel cosmology of the D&D game (see Chapter 5 of the Dungeon Master's Guide). If your campaign uses a different cosmology, you will need to assign different home planes to extraplanar creatures.
Creatures not labeled as extraplanar are natives of the Material Plane, and they gain the extraplanar subtype if they leave the Material Plane. No creature has the extraplanar subtype when it is on a transitive plane; the transitive planes in the D&D cosmology are the Astral Plane, the Ethereal Plane, and the Plane of Shadow.