Mammoth A5E

Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 23 (3d10+7) piercing damage. If the elephant moves at least 20 feet straight towards the target before the attack the target makes a DC 18 Strength saving throw falling prone on a failure.

Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 23 (3d10+7) bludgeoning damage.

The mammoth makes a stomp attack against a prone creature.

Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 10 (1d6+7) bludgeoning damage. If the target is a Large or smaller creature, it is pushed 10 feet away from the mammoth and knocked prone.