What appeared to be a submerged, moss-covered boulder turns out to be some type of monstrous crustacean, with slashing, crushing tentacles.


XP 700 ()

Unaligned Large

Initiative +1


AC 18 (natural armor)

hp: 68 (8d10 + 24)

Resistance: Psychic damage


Speed: 10 ft., swim 30 ft.

Multiattack: A lithonnite attacks twice with tentacles.

Melee Attack—Tentacles: +5 to hit (reach 5 ft.; one creature). Hit: 1d10 + 3 slashing damage. If both attacks hit the same target, it takes an additional 2d6 bludgeoning damage and is grappled and restrained. While the lithonnite has a target grappled, it can attack only that target.


Str 16 (+3), Dex 13 (+1), Con 17 (+3),

Int 4 (–3), Wis 10 (+0), Cha 4 (–3)

Languages: None

Skills: Stealth +3

Senses: Darkvision 60 ft.


Soft Underbelly: A lithonnite’s shell has AC 18. If it can be attacked from underneath, where its body is exposed, its AC is only 11. Its soft body has resistance to bludgeoning damage from nonmagical weapons.

Stony Camouflage: While sitting motionless in water, a lithonnite is impossible to distinguish visually from a moss- covered boulder.


Environment: Temperate and warm ,

Organization: Solitary or pair

Lithonnites are enormous creatures related to mollusks. They live in shallow water both on the surface and . When the lithonnite’s body is at rest in shallow water (2 to 6 feet of depth is its preferred environment), the shell is nearly indistinguishable from any other boulder or natural rock. A lithonnite is always covered with barnacles, moss, seaweed, starfish, and other life, adding to its camouflage.

Most of a lithonnite’s body is encased in a hard shell that rivals plate armor for toughness. Even its eyes are protected by heavy, rocklike protrusions. This shell is nearly as hard as stone, giving the lithonnite excellent protection against enemies. The creature’s tentacles are long enough to reach around the shell and strike effectively in any direction.

It is not possible for the lithonnite to draw its soft body entirely into the shell. If attackers can get underneath the lithonnite, where its squishy flesh is exposed, it’s quite vulnerable. The lithonnite tries to protect itself by staying in shallow water, where it can use the stony lake bottom or a coral reef for protection. A lithonnite can be rolled onto its back with a successful DC 25 Str (Athletics) check, but it will right itself again on its next turn unless it’s somehow prevented from doing so.