Tentacool (5e Creature)
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Small elemental, any alignment
Saving Throws Con +5
Rain Dish. While submerged in water or outside during rain while it has at least 1 hit point, the tentacool regains 5 hit points at the start of each of its turns.
Clear Body. The tentacool is immune to any effect that would cause it to gain disadvantage on attack rolls, ability checks, or saving throws.
Water Pulse. Ranged Spell Attack: +5 to hit, range 20/60 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage. If the target is a creature, it must succeed on a DC 13 Strength saving throw or be pushed back 5 ft.