Monster Manual, page 80
Plesiosaurus CR: 2
Large beast, unaligned
Armor Class: 13 (natural armor)
Hit Points: 68 (8d10+24)
Speed:
4 sq.
, swim: 8 sq.
Skills: Perception +3, Stealth +4
Senses: Passive Perception 13
Challenge Rating: 2
( 450 XP)
Proficiency Bonus: +2
Hold Breath. The plesiosaurus can hold its breath for 1 hour.
Actions
Bite. Melee Weapon Attack: +6 to hit, reach 2 sq., one target. Hit: 14 (3d6 + 4) piercing damage.
This predatory marine reptile and cousin to the dinosaurs attacks any creature it encounters. Its long, flexible neck lets it twist in any direction to deliver a powerful bite.
Suggested Environments
Coastal, Underwater