Ixitxachitl (5e Creature)
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Medium monstrosity, chaotic evil
Water Breathing. Ixitxachitl can breathe only underwater.
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 9 (3d4 + 2) bludgeoning damage.
Sting. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 7 (3d4) piercing damage + poison.
Ixitxachitl (pronounced ish-it-SHACH-itl, although iks-it-ZATCH-i-til or ik-zit-zah-chih-tull are both used) are a race of intelligent, aquatic beings that resemble small manta rays with barbed tails. They have an evil disposition and worship evil powers. They love to hunt marine humanoids, and then sacrifice or devour their catch.
Ixitxachitls live in labyrinthine lairs carved by creatures they've enslaved, and groups of ixitxachitls are led by clerics or vampiric ixitxachitls, who keep others in line using intimidation. They are most often found in oceans, but they can also lair in rivers that run to the sea.
Once they've become established in an area, ixitxachitls wage war against other intelligent creatures that trespass. Those that they capture are used as slaves - including humanoids who have means that allow them to breathe underwater - and slaves can outnumber ixitxachitls two-to-one in large settlements.
Ixitxachitls often worship the demon prince Demogorgon.