Encounters: Anauroch - In or Near the River of Gems (Night)

Merrow (CR 3)

Large Giant (Aquatic)
Alignment: Usually chaotic evil
Initiative: -1 (Dex); Senses: darkvision 60 ft., low-light vision, Listen +2, and Spot +2

AC: 16 (-1 size, -1 Dex, +5 natural), touch 8, flat-footed 16
Hit Dice: 4d8+11 (29 hp)
Fort +6, Ref +0, Will +1

Speed: 40 ft. swim
Space: 10 ft./10 ft.
Base Attack +3; Grapple +12
Attack: Longspear +8 melee
Full Attack: Longspear +8 melee
Damage: Longspear 1d8+7
Special Attacks: -

Abilities: Str 21, Dex 8, Con 15, Int 6, Wis 10, Cha 7
Special Qualities:
Feats: Toughness; Weapon Focus (longspear)
Skills: Listen +2, Spot +2, and Swim +5
Advancement: By character class

Climate/Terrain: Temperate aquatic
Organization: Solitary, pair, gang (2-4); or band (5-8)
Treasure: Standard

Source: Monster Manual

Merrow favor overwhelming odds, sneak attacks, and ambushes to a fair fight. They are intelligent enough to fire ranged weapons first to soften up their foes before closing, but ogre gangs and bands fight as unorganized individuals.

Faerûnian Random Encounters by Region and Locale