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

Not to be Disturbed. During spell cycle rounds, the badgersaur can take one reaction per turn, rather than only one per round.

Siege Mosnter. The badgersaur deals double damage to objects and structures.

Spines. A creature that hits the badgersaur with a melee attack while within 5 feet of it takes 4 (1d8) piercing damage.

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

Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 13 (3d6 + 3) piercing damage.

Claws. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 10 (3d4 + 3) slashing damage.

Tail. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 18 (4d6 + 4) bludgeoning damage, and 8 (2d4 + 3) piercing damage. If the target is a creature, it must succeed on a DC 14 Strength saving throw or be knocked prone.

Cycle. If a spell is cast during a spell cycle round, the badgersaur makes all attacks with advantage until the end of the round. The badgersaur may then move up to its full movement, and make a tail attack.