Sig is the tertiary antagonist of the Buzz Lightyear of Star Command episode "42".
Sig is one of the Valkyran Raiders. It is never elaborated how or when Sig joined the Valkyran Raiders or whether it is something all Valkyrans undergo. Although given even less of a personality than Hilda, Sig is one of Brun's second-in-commands. She seems more feminine and stylish compared to other Valkyrans, though she doesn't seem to consider herself above doing menial tasks or getting her hands dirty.
She first appears when she, Brun and Hilda tried to raid a cargo ship, only for Team Lightyear to arrive to the scene. Vowing revenge on Team Lightyear, Brun orders her posse to retreat as their ship disappears into the unknown.
As Team Lightyear uses a new sensor to detect invisible ships, Brun orders Hilda and Sig ship to fire at their ship. However, the sensor created a new personality known as "42", which allows her to take control of the ship to avoid fire, much to the team's surprise. 42 then takes out the Valkyran ship's tailgate, forcing them to retreat once again.
As XR finally learns about 42's presence, he attempts to tell the rest of the team, but they don't believe him and 42 refuses to speak out to them due to her feelings being hurt by the team. At Star Command, XR and Buzz had a fallout, leaving XR to leave with 42 in the ship. However, the Valkyrans caught wind of their location and use a tractor beam to pull the ship in, taking XR as prisoner. Buzz, Mira and Booster then head to the rescue by using a spare but worn-out ship to get themselves pulled into Brun's ship, as Brun plans to dismantle both of Team Lightyear's ships for a price.
As Team Lightyear manages to rescue XR and escape in their ship, Brun caught wind of their escape and orders her posse to catch them. However, 42 reveals herself to the team and navigates their ship to avoid fire again, this time, blasting Brun's pod to spiral around, much to Sig's shock. Realizing now that they have lost, Sig retreats with Brun and the rest of the Valkyran Raiders into space for good.