9573 Slithraa is a LEGO Ninjago spinner released in late August 2012. The spinner includes a Slithraa Minifigure, a transparent blue Hypnobrai spinner, a spinner crown, Slithraa's character card, four battle cards, the Golden Hypnobrai Staff, a transparent blue Hypno Viper, a chain weapon, and four bricks. It is part of the very last wave of Ninjago spinners.
- This the only Serpentine spinner to use a "spinner crown" that is not designed to look like four coiled snakes. Instead, Slithraa's spinner crown uses a design that is unique to the fourth and final wave of 2012 spinners.