While inside of his puppet Hiruko, Sasori fires it's torpedo-shaped left arm towards the enemy. The arm rotates at high speed, launching the wooden cylinders attached to it. The cylinders then open, each one releasing a large amount of senbon, creating a quick rain of poisoned needles in all directions.
Trivia
- The name of this technique was established in Naruto Shippuden: Ultimate Ninja 4, as it was unnamed in both anime and manga.