Concordant Killer (CR 19)

Large Outsider (Extraplanar)
Alignment: Always neutral
Initiative: +7(+3 Dex, +4 Improved Initiative); Senses: darkvision 60 ft., low-light vision, true seeing, Listen +28, and Spot +28
Languages: Abyssal, Celestial, Common; telepathy 100 ft.

AC: 39 (-1 size, +3 Dex, +19 natural, +4 armor, +4 shield), touch 12, flat-footed 36
Hit Dice: 19d8+115 (200 hp); DR: 10/-
Fort +17, Ref +19, Will +17
Speed: 40 ft. and Fly 90 ft. (good)
Space: 10 ft.; Reach 10 ft.
Base Attack +19; Grapple +31
Attack: Melee: +2 concordant greatsword +29/+24/+19/+14 (3d6+14/17-20) or Melee: 2 slams +26 each (2d8+8)
Special Attacks/Actions:
Attack Options: Cleave, Power Attack, Quicken Spell-Like Ability (greater dispel magic), Quicken Spell-Like Ability (wall of force), concordant greatsword
Abilities: Str 27, Dex 17, Con 23, Int 16, Wis 22, Cha 24
Special Abilities: Immune: acid, cold, electricity, fire, petrification, poison; SR 30; Spell-Like Abilities (CL 19th)
Special Qualities: aligned defenses, know alignment
Feats: Cleave, Improved Critical (greatsword), Improved Initiative, Power Attack, Quicken Spell-Like Ability (greater dispel magic), Quicken Spell-Like Ability (wall of force), Weapon Focus (greatsword),
Skills: Concentration +28, Diplomacy +9, Hide +21, Intimidate +29, Jump +12, Knowledge (arcana) +25, Knowledge (the planes) +25, Listen +28, Move Silently +25, Sense Motive +28, Spellcraft +27 (+29 with scrolls), Spot +28, Survival +6 (+9 on other planes), and Use Magic Device +29 (+31 with scrolls)
Advancement: 20-40 HD (Large)
Climate/Terrain: Any
Organization: Most often solitary, occasionally group (4-5)
Treasure/Possessions: Standard, usually magic items

Source: Monster Manual IV

Possessions: +2 concordant greatsword

True Seeing (Su): As the true seeing spell; continuous; caster level 19th.

Concordant Greatsword (Su): Carried by every concordant killer, these blades are an extension of their carrier's will. Such a blade is treated as though it possessed the anarchic, axiomatic, holy, and unholy special abilities simultaneously. The sword can be sundered (it has hardness 14 and 30 hp), but if the concordant killer relinquishes its grip, the weapon dissipates. A concordant killer can create a new blade as a move action.

If the concordant killer is destroyed, the sword it bears disappears forever.

Aligned Defenses (Su): A concordant killer can increase its defenses against creatures of a specific alignment component (good, evil, law, or chaos). Against attacks made or effects created by creatures of the chosen alignment, this ability grants the concordant killer a +4 deflection bonus to AC and a +4 resistance bonus on saving throws. At will, as a standard action, the concordant killer can change the alignment to which this effect is attuned.

This ability also blocks spells of up to 3rd level cast by creatures of the specified alignment, as a lesser globe of invulnerability spell (CL 19th).(These defensive benefits are not included in the creature's statistics.)

Know Alignment (Su): As the detect chaos, detect evil, detect good, and detect law spells; continuous; caster level 19th. A concordant killer can suppress or resume some or all of this ability as a free action.

Spell-Like Abilities (CL 19th): At will - analyze dweomer (DC 23), greater dispel magic, mage armor; magic missile, Otiluke's resilient sphere (DC 21), shield, greater teleport (self plus 50 lb. of objects only); 3/day - forcecage, greater invisibility, Mordenkainen's sword, Otiluke's telekinetic sphere (DC 25), plane shift (self only), wall of force; 1/day - blasphemy (DC 24), dictum (DC 24), holy word (DC 24), mind blank, word of chaos (DC 24)

Possessing both celestial and demonic heritage, these powerful entities are dispassionate killers who frequently deliver the wrath of the gods. Concordant killers seek always to perfect their killing abilities and, when not in the employ of a higher power, hunt down those they deem worthy prey.

Extraplanar Subtype

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.