Atreyu

Charge. If the unicorn 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.

Innate Spellcasting. The unicorn's innate spellcasting ability is Charisma (spell save DC 14). The unicorn can innately cast the following spells, requiring no components:

At will: detect evil and good, druidcraft, pass without trace

1/day each: calm emotions, dispel evil and good, entangle

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

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

Keen Smell. The panther has advantage on Wisdom (Perception) checks that rely on smell.

Pounce. If the panther moves at least 20 feet straight toward a creature and then hits it with a claw attack on the same turn, that target must succeed on a DC 12 Strength saving throw or be knocked prone. If the target is prone, the panther can make one bite attack against it as a bonus action.

Multiattack. The unicorn makes two attacks: one with its claw and one with its horn or bite.

Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 5 (1d8 + 4) piercing damage.

Claw. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 4 (1d5 + 4) slashing damage.

Horn. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 8 (1d8 + 4) piercing damage.

Healing Touch (3/Day). The unicorn touches another creature with its horn. The target magically regains 11 (2d8 + 2) hit points. In addition, the touch removes all diseases and neutralizes all poisons afflicting the target.

Teleport (1/Day). The unicorn magically teleports itself and up to three willing creatures it can see within 5 feet of it, along with any equipment they are wearing or carrying, to a location the unicorn is familiar with, up to 1 mile away.