Warhorse Warrior (18th)

Trampling Charge. If the horse 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 19 Strength saving throw or be knocked prone. If the target is prone, the horse can make another attack with its hooves against it as a bonus action.

Faithful Steed. When the horse acts as a controlled mount, it can take any action of its rider’s choice, not just Dash, Disengage, or Dodge.

Special Equipment. The sidekick has an Insignia of Claws and a Saddle of the Cavalier.

Improved Critical. The sidekick’s attack rolls score a critical hit on a roll of 19 or 20 on the d20.

Battle Readiness. The sidekick has advantage on initiative rolls.

Improved Defense. The sidekick’s Armor Class increases by 1.

Indomitable (2 / long rest). The sidekick can reroll a saving throw that it fails, but it must use the new roll.

Extra Attack. The sidekick can attack three times, instead of once, whenever it takes the Attack action on its turn.

Hooves. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 13 (2d6 + 6) bludgeoning damage.

Second Wind. The sidekick can use a bonus action on its turn to regain hit points equal to 1d10 + its level in this class. Once it uses this feature, it must finish a short or long rest before it can use it again.

Defender. The sidekick can use its reaction to impose disadvantage on the attack roll of a creature within 5 feet of it whose target isn’t the sidekick, provided the sidekick can see the attacker.