Aqua Deer

Amphibious. The deer can breathe air and water.

Charge. If the deer moves at least 20 feet straight toward a target and then hits it with a horn attack on the same turn, the target takes an extra 9 (2d8) piercing damage. If the target is a creature, it must succeed on a DC 15 Strength saving throw or be knocked prone.

Magic Resistance. The deer has advantage on saving throws against spells and other magical effects.

Magic Weapons. The deer's weapon attacks are magical.

Innate Spellcasting. The deer's innate spellcasting ability is Intelligence (spell save DC 11). The deer can innately cast the following spells, requiring no components:

At will: water walk, shape water, create or destroy water, dancing lights, detect evil and good

1/day each: watery sphere, control water, wall of water

Multiattack. The deer makes three melee attacks: two with its hooves and one with its antlers.

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 13 (2d8+4) piercing damage.

Hooves. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 15 (2d10+4) bludgeoning damage.

Antlers. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 17 (2d12+4) piercing damage.