Dratini (5e Creature)
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Medium dragon, any alignment
Inner Focus. The dratini has advantage on saving throws against being charmed or frightened.
Constrict. Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 6 (1d8 + 2) bludgeoning damage, and the target is grappled (escape DC 12). Until this grapple ends, the creature is restrained, and the snake can't constrict another target.