Keen Smell. The bear has advantage on Wisdom (Perception) checks that rely on smell.

Ice Walk. The undead bear 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.

Multiattack. The bear makes two attacks: one with its bite and one with its claws.

Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 9 (1d8 + 5) piercing damage.

Claws. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 5) slashing damage.

Cold Breath (Recharge 5–6). The undead bear exhales an icy blast in a 30-foot cone. Each creature in that area must make a DC 15 Constitution saving throw, taking 45 (10d8) cold damage on a failed save, or half as much damage on a successful one.