The kamaitachi can use its action to polymorph into a swirl of wintry weather. It can revert back to its true form as a bonus action. Its statistics are the same in each form. Any equipment it is wearing or carrying isn’t transformed. It reverts to its true form when it dies. While a wintry swirl, it has a flying speed of 40 feet, immunity to the grappled, petrified, prone, and restrained conditions, and resistance to bludgeoning, piercing, and slashing damage from nonmagical attacks.

The kamaitachi can enter a hostile creature’s space and stop there. It can move through a space as narrow as 1 inch wide without squeezing.

As a bonus action, the kamaitachi sheathes itself in blowing ice and snow, causing attack rolls against it to have disadvantage. The kamaitachi can use this trait only if it is in snowy terrain. Flyby (Wintry Swirl Form Only). The kamaitachi doesn’t provoke opportunity attacks when it flies out of an enemy’s reach.

The kamaitachi has advantage on Wisdom (Perception) checks that rely on smell.

Until it attacks or uses Wintry Assault, the kamaitachi is indistinguishable from a natural swirl of snow unless a creature succeeds on a DC 15 Intelligence (Investigation) check.