Deep Tentacle (5e Creature)
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Medium undead, unaligned
Proficiency Bonus +2
Mindless. The tentacle is immune to any effects that would read its thoughts or reveal its emotions.
A deep tentacle is a sea snake-like creature, made from a severed tentacle given life through dark magic. They sometimes serve aquatic wizards as familiars. They can be very hard to see while submerged, but they aren't very powerful, usually restraining the foes of their leaders for more threatening allies to take care of.
Undead Nature. A deep tentacle doesn't require air, food, drink, or sleep.