This animal appears in the Monster Manual (2024).
Traits
Water Breathing. The seahorse can breathe only underwater.
Actions
Ram. Melee Attack Roll: +4, reach 5 ft. Hit: 9 (2d6 + 2) Bludgeoning damage, or 11 (2d8 + 2) Bludgeoning damage if the seahorse moved 20+ feet straight toward the target immediately before the hit.
Bonus Actions
Bubble Dash. While underwater, the seahorse moves up to half its Swim Speed without provoking Opportunity Attacks.