Rock Clam

Medium beast, neutral

Armor Class 15 (natural armor)
Hit Points 5 (1d6+1), 9 (2d6+2), 17 (3d8+3), 22 (4d8+4)
Speed 5 ft.

14 (+2) 10 (+0) 12 (+1) 1 (–5) 9 (–1) 3 (–4)

Damage Resistances fire
Senses blindvision 20 ft., passive Perception 9
Languages none
Challenge 1/4 (50 XP) to 1 (200 XP)


  • Natural Camouflage. Rock clams have advantage on Dexterity (Stealth) checks made to hide in rocky terrain.


  • Multiattack. The rock clam makes two Tendril attacks.
  • Tendril. Ranged Weapon Attack: +3 to hit, range 10 ft., one target. Hit: If the target is a creature, it is grappled (escape DC 16). Until this grapple ends the target is restrained, and the rock clam can’t use this Tendril on another target. The victim must succeed at a DC 14 Strength check or be pulled to the clam’s mouth and attacked with a Bite at the start of the rock clam’s next turn. If a target creature is hit with two Tendril attacks it immediately drags its prey into its sharp-toothed maw and bites. A Tendril can be severed by doing slashing damage against an Armor Class of 14. The amount of damage needed depends on the size of the rock clam: 4 hit points, 8 hit points, 12 hit points, 16 hit points.
  • Bite. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: based on size: 5 (1d4+2), 9 (2d4+4), 14 (3d4+6), 18 (4d4+8) piercing damage.


Rock clams are carnivorous land-based monsters that appear as rocks or small boulders 2 to 5 feet in diameter. Their natural camouflage makes them almost indistinguishable from their surroundings.

Rock clams position themselves to ambush their prey in tight spaces and narrow tunnels. When they sense movement within 10 feet, the rock-like creature opens its mouth and lashes out with two tendrils (a rock clam may divide its tendril attacks against multiple opponents).

Rock clams disgorge treasure they cannot digest and there is a 25% chance of 1d3 gems and a 25% chance of 1d3 jewelry in the immediate vicinity. Each rock clam contains a large pearl in its center worth 100 gp – 400 gp depending on the size of the creature. There is a 1 on d6 chance a rock clam has a Black Pearl worth 300 gp – 1,200 gp instead.

Section 15: Copyright Notice

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