Crab with a Legendary Action (5e Creature)
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Crab with a Legendary Action
Tiny beast, unaligned
Amphibious. The Crab can breathe air and water.
Crab. The Crab appears to be a normal tiny crab. If the Crab is in the same space as a swarm of tiny crabs, it can join the swarm, ending its turn. While part of the swarm, it can occupy the same space that the swarm can, and acts on the swarm's turn, controlling and moving with the swarm. While part of the swarm, the Crab is considered hidden, due to being indistinguishable from the rest of the swarm. A creature that succeeds in a Wisdom (Perception) check against a DC of 20 is able to distinguish the crab from the swarm, allowing it to target the crab for spells, attacks and other effects. Otherwise, only the swarm can be targeted, and the crab makes any Saving Throws the swarm would make, and is able to use its Legendary Resistance for the swarm (if the swarm is included in an area of effect, the crab is also affected by it, and the save the crab makes applies for the swarm and itself).
Legendary Resistance (3/Day). If the crab fails a saving throw, it can choose to succeed instead.
Multiattack. The Crab makes 5 attacks with its claws.
Attack. Melee Weapon Attack: +13 to hit, reach 5 ft., one target. Hit: 12 (2d4 + 7) bludgeoning damage.
Crab Frenzy (Recharge 5-6). The crab riles up all the crab swarms within 30ft to briefly form a writhing mass of crabs centred on a point within 30ft., with a radius of 20ft. Any creature in this area that isn't a tiny crab or swarm of tiny crabs must make a Constitution saving throw against a DC of 19, taking 3d8 piercing damage for each swarm that takes part in the frenzy if it fails, half as much on a success. After this, the crabs return to the swarms they originally came from.
The Crab with a Legendary Action can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The Crab with a Legendary Action regains spent legendary actions at the start of its turn.
Detect. The crab makes a Wisdom (Perception) check.
Attack. The crab makes 2 attacks with its claws, and can move up to half its speed.
Command Crabs (Costs 2 Actions). The Crab communicates with any tiny crabs within 300ft, allowing them to form into swarms, move up to their speed, and attack. 2d4 swarms of tiny crabs are formed this way (if there are any swarms of tiny crabs within 60ft of the Crab, reduce the number of swarms formed by the number of existing swarms).
Swarm of Tiny Crabs
Medium swarm of Tiny beasts, unaligned
Damage Resistances Bludgeoning, Slashing, Piercing
Swarm. The swarm can occupy another creature's space and vice versa, and the swarm can move through any opening large enough for a Tiny crab. The swarm can't regain hit points or gain temporary hit points. However, if the swarm enters the space of another Swarm of Tiny Crabs, and both swarms have half or of their hit points or fewer, the other swarm joins this one, causing this swarm's hit points to become the combined current hit points of the two.
Snapping Claws. Melee Weapon Attack: +5 to hit, reach 0 ft., one target in the swarm's space. Hit: 14 (4d6) piercing damage, or 7 (2d6) piercing damage if the swarm has half of its hit points or fewer. If the target is a creature, crabs cling on to its body, and the creature takes 3 (1d6) piercing damage at the start of each of its turns. Any creature can use an action to kill or remove the crabs with fire or a weapon that deals piercing damage, causing 1 damage of the appropriate type to the target.