Hermit Crabs

Hermit Crab

Huge monstrosity

Armour Class 19 (natural armour)
Hit Points 161 (14d12 + 70)
Speed 40 ft.

20 (+5) 6 (-2) 20 (+5) 3 (-4) 12 (+1) 10 (+0)

Damage Immunities Radiation
Damage Resistances Cold, Fire, Energy, Electrical
Condition Immunities Radiation Sickness
Senses darkvision 120 ft., tremorsense 60 ft., passive Perception 11
Languages none
Challenge 15 (13,000 XP)

Amphibious. The hermit crab can breathe air and water.

Crush. The hermit crab automatically hits when it makes a claw attack against a target it has grappled, and deals maximum (17) damage.

Curl Up. When the hermit crab takes the Dodge action, its speed drops to 0 and it has disadvantage on Dexterity saving throws. However, it gains resistance to all forms of damage and any critical hit against it is treated as a normal hit.

Legendary Resistance (2/day). If the hermit crab fails a saving throw, it can choose to succeed instead.

Tough. The hermit crab reduces the damage of bludgeoning, piercing, or slashing attacks by 3.


Multiattack. The hermit crab makes two attacks.

Claws. Melee weapon attack: +11 to hit, reach 10 ft., one target. Hit: 15 (3d6 + 5) bludgeoning damage, and the target is Grappled (escape DC 19). The crab has two claws, each of which can grapple only one target.

Slam. Melee weapon attack: +11 to hit, reach 5 ft., one target. Hit: 22 (3d12 + 5) bludgeoning damage.

Legendary Actions

The hermit crab can take 3 legendary actions, choosing from the options below. Only one legendary action can be used at a time, and only at the end of another creature’s turn. Spent legendary actions are regained at the start of each turn.

Claw. The hermit crab makes a claw attack.

Detect. The hermit crab makes a Wisdom (Perception) check.

Charge (costs 2 actions). The hermit crab moves up to its speed then makes a melee attack.

Smash (costs 2 actions). The hermit crab makes an attack. The target and each creature adjacent to it must succeed on a DC 19 Dexterity saving throw or be knocked prone.

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