Bardic Half-Electrum Dracolich Highland Cow

Trampling Charge. If the cow moves at least 20 feet straight toward a creature and then hits it with a hooves attack on the same turn, that target must succeed on a DC 18 Strength saving throw or be knocked prone If the target is prone, the cow can make another attack with its hooves against it as a bonus action.

Rejuvenation. If it has a phylactery, the destroyed cow gains a new body in 1d10 days, regaining all its hit points and becoming active again. The new body appears within 5 feet of the phylactery.

Spellcasting. The cow is a 17th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 18, +10 to hit with spell attacks). The cow has the following bard spells prepared:

Cantrips (at will): light, mage hand, minor illusion, thunderclap

1st level (4 slots): animal friendship, earth tremor, sleep, thunderwave 

2nd level (3 slots): dragon's breath, shatter, silence

3rd level (3 slots): glyph of warding, haste, sending, thunder step

4th level (3 slots): no spells

5th level (2 slots): animate objects, awaken, dream, holy weapon, raise dead, teleportation circle

6th level (1 slot): find the path

7th level (1 slot): regenerate, resurrection

8th level (1 slot): no spells

9th level (1 slot): true polymorph

Magic Weapons. The cow's weapon attacks and breath weapons are magical.

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

Turn Resistance. The cow has advantage on saving throws against any effect that turns undead.

Hooves. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage.

Gore. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) [damage type] damage. 

Countercharm. The cow performs until the end of its next turn. During that time, the cow and any friendly creatures within 30 ft. that can hear it gain advantage on saving throws against being frightened or charmed.

Breath Weapons (Recharge 5–6). The cow uses one of the following breath weapons.

Frostflame Breath. The cow exhales an icy blast of fire in a 15-foot cone. Each creature in that area must make a DC 18 Dexterity saving throw, taking 11 (2d10) fire damage and 9 (2d8) cold damage on a failed save, or half as much damage on a successful one.

Paralyzing Breath. The cow exhales paralyzing gas in a 15-foot cone. Each creature in that area must succeed on a DC 18 Constitution saving throw or be paralyzed for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

The cow can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The cow regains spent legendary actions at the start of its turn.

Detect. The cow makes a Wisdom (Perception) check.

Hooves. The cow makes one attack with its hooves.

Move (Costs 2 Actions). The cow moves up to its speed without provoking opportunity attacks.