Guards of a Sahuagin tribe are quite the experts of combat.

Male Sahuagin Fighter 4 (CR 5)

Medium Monstrous Humanoid (Aquatic)
Init +3; Senses Blindsense (30 feet), Darkvision (60 feet); Perception +7

AC 21, touch 14, flat-footed 17 (+2 armor, +3 Dex, +5 natural, +1 dodge)
hp 67 (6d10+28)
Fort +10, Ref +7, Will +6
Weakness Light Blindness

Speed 30 ft., Swimming (60 feet)
Melee Bite (Sahuagin) +5 (1d4+2) and Claw x2 (Sahuagin) +5 x2 (1d4+2) and Masterwork Trident +12/+7 (1d8+4) and Unarmed Strike +10/+5 (1d3+4)

Str 18, Dex 16, Con 18, Int 15, Wis 15, Cha 10
Base Atk +6/+1; CMB +10; CMD 24
Feats Combat Reflexes (4 AoO/round), Dodge, Great Fortitude, Toughness +6, Vital Strike, Weapon Focus: Trident
Skills Handle Animal +5, Intimidate +8, Perception +7, Ride +8, Sense Motive +5, Stealth +8, Survival +11, Swim +21
Languages Aquan, Common; Speak with Sharks
SQ Armor Training 1 (Ex), Blood Frenzy (1/day) (Ex), Bravery +1 (Ex)
Combat Gear Masterwork Trident, Leather; Other Gear Potion of Cure Moderate Wounds

Armor Training 1 (Ex) Worn armor -1 check penalty, +1 max DEX.
Blindsense (30 feet) (Ex) Sense things and creatures without seeing them.
Blood Frenzy (1/day) (Ex) Once per day, a sahuagin that takes damage in combat can fly into a frenzy in the following round. It gains +2 Constitution and +2 Strength, but takes a -2 penalty to its AC. The frenzy lasts as long as the battle or 1 minute, whichever is shorter.
Bravery +1 (Ex) +1 Will save vs. Fear
Combat Reflexes (4 AoO/round) You may make up to 4 attacks of apportunity per round, and may make them while flat-footed.
Darkvision (60 feet) You can see in the dark (black and white vision only).
Light Blindness (Ex) Blinded for 1r in bright light, dazzled as long as they remain in it.
Speak with Sharks (Su) A sahuagin can communicate telepathically with sharks to a distance of 150 feet. This communication is limited to simple concepts, such as 'come here,' 'defend me,' or 'attack this target.'
Swimming (60 feet) You have a Swim speed.
Vital Strike Standard action: x2 weapon damage dice.