Ice Mammoth (5e Creature)
From D&D Wiki
Huge monstrosity, unaligned
Cold Body. A creature that touches the mammoth or hits it with a melee attack while within 5 feet of it takes 9 (2d8) cold damage.
Ice Walk. The mammoth can move across and climb icy surfaces without needing to make an ability check. Additionally, difficult terrain composed of ice or snow doesn't cost it extra movement.
Trampling Charge. If the mammoth moves at least 20 feet straight toward a creature and then hits it with a gore attack on the same turn, that target must succeed on a DC 22 Strength saving throw or be knocked prone. If the target is prone, the mammoth can make one stomp attack against it as a bonus action.
Gore. Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 26 (4d8 + 8) piercing damage plus 9 (2d8) cold damage.
Stomp. Melee Weapon Attack: +14 to hit, reach 5 ft., one prone creature. Hit: 30 (4d10 + 8) bludgeoning damage plus 9 (2d8) cold damage.
Ice mammoths are massive elephantine creatures composed partly of ice and snow. If need be, an ice mammoth can survive by eating nothing more than ice and snow.