Mindwitness* (CR 16)

Large Aberration
Alignment: Usually lawful evil
Initiative: +6 (+2 Dex, +4 Improved Initiative); Senses: all-around vision, darkvision 60 ft.,, Listen +20, and Spot +24
Languages: Their own language and Common, telepathy 100 ft.

AC: 27 (-1 size, +2 Dex, +16 natural), touch 11, flat-footed 24
Hit Dice: 11d8+44 (93 hp)
Fort +9, Ref +5, Will +13
Speed: 5 ft., fly 20 ft. (good)
Space: 10 ft./5 ft.
Base Attack +8; Grapple +12
Attack: Eye rays +9 ranged touch or tentacle +2 melee (1d6)
Full Attack: Eye rays +9 ranged touch and four tentacles +2 melee (1d6)
Damage: -
Special Attacks/Actions: Extract, eye rays, improved grab, mind blast
Abilities: Str 10, Dex 14, Con 18, Int 21, Wis 19, Cha 19
Special Qualities: antimagic cone, flight, SR 21
Feats: Alertness; Flyby Attack; Great Fortitude; Improved Initiative; Iron Will
Skills: Hide +12, Knowledge (arcana) +19, Listen +20, Move Silently +9, Search +23, Spellcraft +14, Spot +24, Survival +4 (+6 following tracks), and Use Magic Device +4 (+6 scrolls)
Advancement: 12-16 HD (Large); 17-3 3 HD (Huge)
Climate/Terrain: Underground
Organization: Solitary, pair, or cluster (3-6)
Treasure/Possessions: Double standard

Source: Underdark

Extract (Ex): A mindwitness that begins its turn with all four tentacles attached and wins a grapple check automatically extracts the opponent's brain, instantly killing that creature. This power is useless against constructs, elementals, oozes, plants, and undead. Extraction is not instantly fatal to foes with multiple heads, such as ettins and hydras.

Eye Rays (Su): Each of a mindwitness's ten small eyes can produce a magical ray once per round as a free action. During a single round, the creature can aim only three eye rays at targets in any one 90-degree arc (up, forward, backward, left, right, or down). The remaining eyes must aim at targets in other arcs or not at all. A mindwitness can tilt and pan its body each round to change which rays it can bring to bear in any given arc. Each eye's effect resembles a spell (caster level 13th), but follows the rules for a ray. Each ray has a range of 150 feet and a save DC of 19. The save DC is Charisma-based. The ten rays are charm monster, charm person, disintegrate, fear, finger of death, flesh to stone, inflict moderate wounds, sleep, slow, and telekinesis. See the Beholder.

Improved Grab (Ex): To use this ability, a mindwitness must hit a creature of its size category or smaller with its tentacle attack. It can then attempt to start a grapple as a free action without provoking an attack of opportunity. If it wins the grapple check, it establishes a hold and attaches the tentacle to the opponent's head. A mindwitness can grab a Huge or larger creature, but only if it can somehow reach the foe's head. If a mindwitness begins its turn with at least one tentacle attached, it can try to attach its remaining tentacles with a single grapple check. The opponent can escape with a single successful grapple check or an Escape Artist check, but the mindwitness gets a +2 circumstance bonus for every tentacle that was attached at the beginning of the opponent's turn.

Mind Blast (Sp): Once per day, a mindwitness can produce a mind blast in a cone 40 feet long. Anyone caught in this area must make a DC 19 Will save or be stunned for 1d4 rounds. The save DC is Charisma-based. This ability is the equivalent of a 4th-level spell.

Psionics (Sp): 3/day-charm monster (DC 18), detect thoughts, levitate, suggestion (DC 17). Caster level 8th. The save DCs are Charisma-based.

All-Around Vision (Ex): A mindwitness's many eyes give it a +4 racial bonus on Search and Spot checks, and it can't be flanked.

Antimagic Cone (Su): A mindwitness's central eye continually produces a 150-foot cone of antimagic. This functions just like antimagic field (caster level 13th). All magical and supernatural powers and effects within the cone are suppressed - even the beholder's own eye rays. Once each round, during its turn, the mindwitness decides whether the antimagic cone is active or not (the mindwitness deactivates the cone by shutting its central eye).

Flight (Ex): A mindwitnesses body is naturally buoyant. This buoyancy allows it to fly at a speed of 20 feet and grants it a permanent feather fall effect (as the spell) with personal range.

Telepathy (Su): A mindwitness can communicate telepathically with any creature within 100 feet that has a language.

Mindwitnesses begin combat by using mind blast on their foes, then follow up with their devastating eye rays. They usually refrain from attempting to extract the brains of creatures that have not been stunned or otherwise befuddled.