Umber Hulk
What looks like a chitin-covered ape comes lumbering down the tunnel. The chattering of its pincers echo down the wall, alerting its brothers that there is food to be had. Long, heavy claws scratch on the floor in a sloping gait. All you can think to do is run back toward the surface, back where its safe... until you see the thousands upon thousands of reflections in its multi-faceted eyes and...
And...
and...
You know, there was something really important you had to do, but now that these big bony guys have you over their shoulders, you can't remember what it was.
Umber Hulk
CR 7
XP: 3,200
CE Large Aberration
Init: +1; Senses: Darkvision 60 ft., tremorsense 60 ft.; Perception +13
DEFENSE:
AC: 18, Touch 10, Flat-Footed 17 (-1 size, +1 Dex, +8 natural)
HP: 95 (10d8+50)
Fort: +9; Ref: +4; Will: +7
OFFENSE:
Speed: 20 ft, burrow 20 ft.
Melee: 2 claws +12 (1d8+6) and bite +12 (1d8+3)
Space: 10 ft.; Reach: 10 ft.
Special Attacks: Gaze (DC 15 or be confused for 2d6 rounds)
STATISTICS:
Str 23, Dex 13, Con 19, Int 11, Wis 11, Chr 11
Base Atk: +7; CMB: +14; CMD: 25
Feats: Great Fortitude, Improved Natural Attack (claws), Multiattack, Power Attack, Toughness
Skills: Acrobatics +14, Climb +19, Knowledge (dungeoneering) +13, Perception +13
Languages: Undercommon
ECOLOGY:
Environment: Underground
Organization: Solitary or cluster (2-4)
Treasure: Standard
Role: Combat
Source: MM1, pg. 249
Examples of brute force plus mindless devotion, umber hulks are aberrations, warped from equal parts beetle, cockroach and mountain ape. Void of much in the way of ambition, but intelligent enough to follow complex orders, umber hulks are easily bred in captivity and naturally organize themselves into structured units, giving more intelligent denizens of darkness a steady supply of obedient grunts.