Encounters: Thunderpeaks South

Yuan-Ti, Pureblood (CR 5)

Medium Monstrous Humanoid
Alignment: Usually chaotic evil
Initiative: +5 (+1 Dex, +4 Improved Initiative); Senses: darkvision 60 ft., Listen +4, and Spot +4
Languages: Yuan-ti, Common, Draconic, and Abyssal

AC: 17 (+1 Dex, +1 natural, +3 masterwork studded leather, +2 masterwork heavy shield), touch 11, flat-footed 16
Hit Dice: 4d8 (18 hp)
Fort +1, Ref +5, Will +4

Speed: 30 ft.
Space: 5 ft./5 ft.
Base Attack +4; Grapple +4
Attack: Masterwork scimitar +5 melee; or masterwork longbow +6 ranged
Full Attack: Masterwork scimitar +5 melee; or masterwork longbow +6 ranged
Damage: Masterwork scimitar 1d6/18-20; or masterwork longbow 1d8/x3
Special Attacks: Spell-like abilities

Abilities: Str 11, Dex 13, Con 11, Int 12, Wis 10, Cha 12
Special Qualities: Alternate form, detect poison, SR14
Feats: Alertness; Blind-fight; Dodge; Improved Initiative
Skills: Concentration +7, Disguise +4*, Hide +3, Knowledge (any one) +5, Listen +4, and Spot +4
Advancement: By character class

Climate/Terrain: Warm forest and underground
Organization: Solitary, pair, gang (2-4), troupe (2-13 purebloods, 2-5 halfbloods, and 2-4 abominations); or tribe (20-160 purebloods, 10-80 halfbloods, and 10-40 abominations)
Treasure: Double Standard

Source: Monster Manual

Yuan-ti are geniuses and fight as such. They plan elaborate traps and utilize their surroundings superbly in combat, preferring ambushes to direct confrontation. They also prefer ranged attacks and spells to melee, and they liberally use cause fear and aversion to keep foes at a distance.

In a mixed group, the least valuable and powerful attack first. This means that the purebloods go before the halfbloods, which go before the abominations. The group leader may order particular members forward before others if that makes for better strategy.

Spell-like Abilities: (Human-headed) 1/day - animal trance, cause fear, deeper darkness, entangle, neutralize poison, suggestion, and polymorph other. These abilities are as the spells cast by an 8th-level sorcerer (save DC 13 + spell level).

Psionics (Sp): All yuan-ti can produce the following effects at will:
Detect Poison: As the spell cast by a 6th-level sorcerer.
Alternate Form: The yuan-ti can assume the form of a Tiny to Large viper (see the Snake entry). If the yuan-ti has a poisonous bite of its own, it uses its own or the viper's poison, whichever is more potent.
Chameleon Power: The yuan-ti can change the coloration of itself and its equipment to match its surroundings.
Produce Acid: The yuan-ti can exude acid from its body, dealing 1d6 points of damage to anything it touches. The acid becomes inert when it leaves the yuan-ti's body.
Aversion: The yuan-ti creates a compulsion effect targeting one creature within 30 feet. The subject must succeed at a Will save (DC 17) or gain an aversion to snakes for 10 minutes. Affected subjects must stay at least 20 feet from any snake or yuan-ti, alive or dead; if already within 20 feet, they move away. A subject can overcome the compulsion by succeeding at another DC 17 Will save, but still suffers deep anxiety. This causes a -4 reduction to Dexterity until the effect wears off or the subject is no longer within 20 feet of a snake or yuan-ti. This ability is otherwise similar to antipathy as cast by a 16th-level sorcerer.

Skills: Yuan-ti using chameleon power receive a +8 circumstance bonus to Hide checks.

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