|Prototype Model Unit XJ-8|
|Age||She is younger than XJ-9 & she is older than XJs 1-7.|
|Likes|| The XJ-Sisters|
her brute strength
fighting against villains
XJ-7 (younger sisters)
XJ-9 (older sister)
|Enemies|| Dr. Locus|
|First appearance||Sibling Tsunami|
|Voiced by:||Audrey Wasilewski|
She is the largest out of the nine XJ-series robots. Resembling a large, bulky, darker blue version of XJ-7 with two belly bolts, small pigtails, and a non-expressive face.
XJ-8 is a bit of a tomboy. She prefers using her brute strength over weapons and strategy. She also pretended to act as Jenny's (unwanted) "date" to the Fake Prom in There's No Place Like Home School.
Sibling Tsunami (Her first appearance)
Agent 00' Sheldon (No Lines)
Escape from Cluster Prime (Brief Cameo)
There's No Place Like Home School (Brief Appearance)
Labor Day (Brief Cameo)
- She is the strongest of the XJ sisters due to her brute strength. However, her reliance on it is what puts her below Jenny.
- It is likely that Dr. Wakeman turns her on from time to time judging by her appearance in There's No Place Like Homeschool.
- She is closest to age with Jenny but still believes she is the older sister because of her size. (Contrary to what Jenny says, XJ-8 is technically older than she is, seeing as she was built before Jenny.)
- Wakeman had to make XJ-8 stronger because she had to take most of Jenny's super strength out to make room for her teenage adaption. Accoring her, XJ-9 was made weaker than XJ-8 because she was so strong that there's was no space on her personality for having teenage weaknesses or humor sense.
- Because she's been off for a long time she has had a hard time adapting to human cultures this is shown when she tried to punish a little girl for attacking a paper pig, and blew up the pinata when she was asked to break it.
- She is a taller, muscular, bulky version of XJ-9.
- She does show emotion from time to time (mostly shown in her eyes).