5e SRD:Giant Sea Horse
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Giant Sea Horse
Large beast, unaligned
Charge. If the sea horse moves at least 20 feet straight toward a target and then hits it with a ram attack on the same turn, the target takes an extra 7 (2d6) bludgeoning damage. If the target is a creature, it must succeed on a DC 11 Strength saving throw or be knocked prone.
Water Breathing. The sea horse can breathe only underwater.
Ram. Melee Weapon Attack: +3 to hit, reach 5 ft., one creature. Hit: 4 (1d6 + 1) bludgeoning damage.
Like their smaller kin, giant sea horses are shy, colorful fish with elongated bodies and curled tails. Aquatic elves train them as mounts.