In Brief: Space Sword Blaster is Sailor Neptune's second attack in the anime and the first to use her Talisman, the Space Sword. The sword could also be used to physically attack but this isn't necessarily a use of the Space Sword Blaster attack or a special attack at all.

Cultural: The Space Sword is actually based on one of the Three Sacred Treasures of Japan, the Kusanagi. Interestingly enough, this real life sword was said to have the power to control the wind which so happens to be Sailor Uranus' ruling element and suggests that those energy blasts that fire out of the sword during the attack could in fact be some kind of wind energy attack.

The Attack: Space Sword Blaster doesn't have the traditional stock animation sequence like so many of the other attacks do, instead on the few times it was used it was done in real time against a stylised background.

Sailor Uranus basically swings the Space Sword at her targets which releases energy (possibly wind energy) blasts with each swipe.