Trampling Charge. If the elephant moves at least 20 ft straight toward a creature and then hits it with a gore attack on the same turn, that target must succeed on DC 12 Strength saving throw or be knocked prone. If the target is prone, the elephant can make one stomp attack against it as a bonus action.
Gore. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 9-19-30 3d8+6 piercing Damage.
Stomp. Melee Weapon Attack: +8 to hit, reach 5 ft., one prone target. Hit: 9-22-36 3d10+6 bludgeoning damage.