Aurelion Warhorse

Battle-Trained Mount. While carrying a rider, the warhorse can make one hooves attack as part of its trampling charge even if it is controlled. If left without a rider, the warhorse remains stationary and takes no actions unless attacked, commanded, or frightened by extraordinary means.

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 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.

Hooves. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) bludgeoning damage.