Dolphin

Medium Beast, Unaligned

AC: 12

Initiative: +1 (11)

HP: 11 (2d8 + 2)

Speed: 0 ft., swim 60 ft.

STR
14 (+2)
DEX
13 (+1)
CON
13 (+1)
INT
6 (-2)
WIS
12 (+1)
CHA
7 (-2)

Skills: Perception +3

Senses: blindsight 60 ft., Passive Perception 13

CR: 1/8 (XP 25; PB +2)

Habitat: Coastal, Underwater

Hold Breath.

The dolphin can hold its breath for 20 minutes.

Actions

Slam.

Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) bludgeoning damage. If the dolphin moved at least 30 feet straight toward the target immediately before the hit, the target takes an extra 3 (1d6) bludgeoning damage.

Find this creature in the encounter builder

Dolphin

Source: Mordenkainen Presents: Monsters of the Multiverse, p. 97 - Licenses and attribution