Anomolocaris (5e Creature)
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Medium beast, unaligned
Water breathing This creature can only breath under water
Armor plating This creature has a damage threshold (see dmg pg 247) of 10 while this creature is at full hit points.
Multiattack. The Giant Anomolocaris makes 2 Appendage slash attacks.
Ram. Melee Attack: +1 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 1) bludgeoning damage.
Appendage slash. Melee Attack: +4 to hit, reach 5ft., one target. Hit: 10 (1d6 + 2) piercing damage. If the Giant anomolocaris hits both apendage slash attacks against the same creature it is grappled.
A rather large for a Cambrian organism that supposedly went extinct, until billions of years later it has been found among the realms. In its time it was one of the most vicious predetors. But then things evolved to be bigger throwing it out of the competition and letting other larger organisms rule. This version of it is much larger then the old Anomolocaris's being up to 6 feet long.