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Mantis Shrimp, Reefhammer

Reefhammer CR 18

This brightly colored crustacean looks like a large lobster with cruel pincers poised at its fore.

XP 153,600
N Huge vermin (aquatic)
Init +8; Senses darkvision 60 ft., incredible sight; Perception +36


EAC 32; KAC 34
Fort +21, Ref +19, Will +16; DR 10/epic; Immunities vermin immunities; Resistances sonic 10


Speed 30 ft., swim 40 ft.
Melee pincer +32 (6d6+29 B & S plus grab and sonic burst)
Multiattack 4 pincers +26 (4d8+29 B & S plus grab and sonic burst)
Offensive Abilities brilliant flash, shattering strike, sonic burst


Str +11, Dex +8, Con +6, Int —, Wis +1, Cha +3
Skills Athletics +36, Stealth +31
Other Abilities mindless


Brilliant Flash (Ex)

Whenever a reefhammer mantis creates a sonic burst, it unleashes a blinding flash. Creatures within 20 feet must succeed at a DC 23 Fortitude save or be blinded for 1 round. Mantis shrimp and sightless creatures are immune to this effect.

Incredible Sight (Ex)

A reefhammer mantis’s eyes pick up colors well beyond those visible to humans, and it can see perfectly in all light conditions, including supernatural darkness. As long as a reefhammer shrimp does not have the blinded condition, it is treated as having blindsight 60 feet.

Sonic Burst (Ex)

A reefhammer mantis attacks with such extreme speed that its pincers issue a concussive blast of light and force when they snap closed. Each time a reefhammer shrimp makes a pincer attack, whether it hits or misses, each creature in a 20-foot-radius centered on the attack’s target takes 3d6 sonic damage and must succeed at a DC 23 Reflex save or be Stunned”>stunned for 1 round. A creature that succeeds at this save is immune to the stun effect from additional sonic bursts from a reefhammer shrimp until the mantis shrimp’s next turn, but it still takes sonic damage from additional sonic bursts. The Reefhammer is immune to this effect.

Shattering Strike (Ex)

A reefhammer mantis deals double damage against objects. When it makes a sunder attempt against an attended object, it affects the creature bearing the object with its sonic burst ability.


Environment warm oceans
Organization solitary

Though the colorful shells of giant mantis shrimp are beautiful to behold, the sight of one often means death. These apex predators prowl massive coral reefs, from tide pools and coastal shallows to the deep rifts and passes off the continental shelf, competing for territory with karkinoi and shark eater crabs. Reefhammer shrimp grow over 20 feet long and weigh over two tons.

Section 15: Copyright Notice

Alien Bestiary (Starfinder) © 2018, Legendary Games; Lead Designer: Jason Nelson. Authors: Anthony Adam, Kate Baker, John Bennet, Eytan Bernstein, Robert Brookes, Russ Brown, Duan Byrd, Jeff Dahl, Robyn Fields, Joel Flank, Matt Goodall, Robert J. Grady, Jim Groves, Steven T. Helt, Thurston Hillman, Tim Hitchcock, Nick Hite, Daniel Hunt, Mike Kimmel Marshall, Isabelle Lee, Jeff Lee, Lyz Liddell, Jason Nelson, Richard Pett, Tom Phillips, Alistair J. Rigg, Alex Riggs, Wendall Roy, Mike Shel, Neil Spicer, Todd Stewart, Russ Taylor, Rachel Ventura, Mike Welham, George Loki Williams, Scott Young.