Yuan-Ti Holy Guardian (CR 8)

Medium Monstrous Humanoid
Alignment: Usually chaotic evil
Initiative: +5 (+1 Dex, +4 Improved Initiative); Senses: darkvision 60 ft., scent, Listen +17, and Spot +17

AC: 20 (+1 Dex, +7 natural, +2 masterwork heavy shield), touch 11, flat-footed 19
Hit Dice: 8d8+16 (52 hp)
Fort +4, Ref +7, Will +10
Speed: 30 ft., climb 20 ft., swim 20 ft.
Space: 5 ft./5 ft.
Base Attack +8; Grapple +12
Attack: Masterwork scimitar +12 melee or masterwork composite longbow (+4 Str bonus) +9 ranged
Full Attack: Masterwork scimitar +12/+7 melee and bite +5 melee or masterwork composite longbow (+4 Str bonus) +9/+4 ranged
Damage: Masterwork scimitar 1d6+4/18-20, bite 1d6+2 plus poison, masterwork composite longbow (+4 Str bonus) 1d8+4/x3
Special Attacks/Actions: Constrict 1d6+6, improved grab, poison, spell-like abilities, venomous tentacles
Abilities: Str 19, Dex 13, Con 15, Int 19, Wis 19, Cha 17
Special Qualities: Alternate form, chameleon power, detect poison, SR 18
Feats: Alertness; Blind-fight; Dodge; Improved Initiative; Mobility
Skills: Climb +11, Concentration +13, Craft (any) +16, Hide +10, Knowledge (religion) +15, Listen +17, Spot +17, and Swim +10
Advancement: By character class
Climate/Terrain: Warm forests
Organization: Solitary, pair, gang (3-4), or guard detail (3-12)
Treasure/Possessions: Double standard

Source: Serpent Kingdoms

A holy guardian fights cunningly, seeking cover and ceding areas as needed in order to encircle, outflank, or otherwise trap intruders.

Constrict (Ex): On a successful grapple check, a holy guardian deals 1d6+6 points of damage.

Improved Grab (Ex): To use this ability, a holy guardian must hit with its bite 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 can constrict.

Poison (Ex): Injury, Fortitude DC 16, initial and secondary damage 1d6 Con. The save DC is Constitution-based.

Spell-Like Abilities: At will- animal trance (DC 15), cause fear (DC 15), entangle (DC 15); 3/day- deeper darkness, dispel magic, neutralize poison (DC 18), resist energy (self only), suggestion (DC 17); 1/day- baleful polymorph (DC 19; into snake form only). Caster level 11th. The save DCs are Charisma-based.

Venomous Tentacles (Sp): Once per day, a holy guardian can produce an effect that functions like the Evard's black tentacles spell, except that the tentacles also deliver poison (contact, Fortitude DC 21, initial and secondary damage 1d6 Con) during each round of grappling. This ability is the equivalent of an 8th-level spell.

Alternate Form (Sp): A holy guardian can assume the form of a Tiny to Large viper as a psionic ability. The holy guardian loses its constrict ability in viper form but uses its own poison or its bite attack.

Chameleon Power (Sp): A holy guardian can psionically change the coloration of itself and its equipment to match its surroundings, gaining a +10 circumstance bonus on Hide checks.

Detect Poison (Sp): A holy guardian can use detect poison as the spell (caster level 6th) at will.

Skills: A holy guardian receives a +8 racial bonus on Climb checks and can always choose to take 10 on Climb checks, even if rushed or threatened. A holy guardian has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.