Roxie is a cyberdog which can be made at the X-8 research center through splicing a dog and a robot. Unlike other companions, it is possible for Roxie to die, even when not playing on Hardcore mode. However, she can be revived by creating her again at the X-8 splicing facility (You will have to use the "clear the splicing area" command even if nothing is on the actual platform before you can splice anything else).
The holotape to splice dogs and robots is found on a large table downstairs near the institutional test facility door in X-8. To create Roxie, enter the X-8 splicing facility, which is found down a hallway to the left of the entrance of the X-8 facility. Once you go through the door in the left hallway there will be a terminal in which you can use the splicing holotapes.
Roxie does not use the companion wheel, you must talk to her to have her follow you or to make her leave. Roxie only follows you around the X-8 facility and will not follow you outside of the facility. If you leave the area, Roxie will stay near the entrance inside the X-8 facility.
There, she ran across Rex at the Kings School of Impersonation. His brain was failing. That was all right, he was still smarter than the Think Tank. The two of them constructed a litter of cyberpups, a small army of Boston terrifiers that gnawed and devoured anything in their path.
Roxie created and Rex is alive, but not obtained as a companion.
There, she ran across Rex, who had been following the Courier, just as she had. They barked for a while, and realized they had a lot in common. The two of them constructed a litter of cyberpups, a small army of Boston terrifiers that gnawed and devoured anything in their path.
Roxie created and Rex is alive and a companion on standby.
There, she ran across the corpse of Rex. She dragged him back to the Big Empty and had him rebuilt for company. The two of them constructed a litter of cyberpups, a small army of Boston terrifiers that gnawed and devoured anything in their path.
Roxie is limited to her bite attack, and does not have the sonic bark weapon the other Big MT cyberdogs do.
Though only a temporary due to her location limitation, Roxie is the only companion in Old World Blues add-on.
She's the only companion who doesn't provide perks to the Courier.
Roxie will not do her "good" ending if you have just had her follow you around, it has to be through at least 1 of the X-8 training missions.
Once you have recruited Roxie you can use the coc console command to get back to the Mojave, there she will be a permanent companion who cannot be dismissed. She also does not count towards the limit of companions you can have, allowing you to have up to three at once. It isn't tested what happens if you re-enter X-8 however Roxie does travel to add-on locations with the player.
If Roxie dies, you can create another in the splicing lab with the same name.