Sources
CR
Type
Size
Alignment
Movement

Sharkbody Abomination

Large Aberration, Unaligned

Armor Class 12 (natural armor)
Hit Points 45 (6d10 + 12)
Speed 20 ft., swim 40 ft.
STR
18
+4
DEX
13
+1
CON
15
+2
INT
1
-5
WIS
10
+0
CHA
4
-3
Skills Perception +2
Senses blindsight 30 ft., passive Perception 12
Languages
Challenge 2 (450 XP)

Traits

Blood Frenzy. The abomination has advantage on melee attack rolls against any creature that doesn't have all its hit points.

Water Breathing. The abomination can breathe only underwater.

Limited Amphibiousness. The abomination can breathe air and water, but it needs to be submerged at least once every 4 hours to avoid suffocating.

Actions

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit:13 (2d8 + 4) piercing damage.

Lore

The sahuagin shaman Selachai tapped into Uk'otoa's magic to wreak vengeance on the shark hunters of Palma Flora. The unfortunate hunters who failed to escape were transformed into monstrosities with coarse grayish skin, the head of a shark, and a muscular, humanoid physique. These creatures possess all their previous intelligence and personality, but they respond to the control of their sahuagin masters' Shark Telepathy.