Horse, War

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 14 STR save or be knocked prone. If the target is prone, the horse can make another Hooves attack against it as a bonus action.

Hooves. _Melee Weapon Attack:_ +6 to hit, reach 5 ft., one target. _Hit:_ 8 (1d8+4) bludgeoning damage.

Trained Shift. If the horse's rider is subjected to an effect that would knock it prone or dismount it, the horse can shift its body to assist the rider. The rider has advantage on the check or save to avoid the effect.