Juliana Sandoval was Roberto Da Costa's girlfriend at the time he first discovered his mutant powers. She was watching him participating in a soccer game, along with this father, Emmanuel Da Costa, when Roberto was brutally fouled and then beaten by a rival player. It was then that Roberto's power first manifested, throwing the spectators and players into a panic; Juliana just barely managed to reach Roberto before he collapsed, and held him in her arms, crying.
This manifestation attracted the attention of Donald Pierce, who was embarging on a campaign to destroy all mutants, and of Professor Professor Charles Xavier. While the Professor sent his friend Moira MacTaggert along with Karma and Mirage to take Roberto to safety, Pierce sent a team of mercenaries to eliminate him, but Roberto escaped. Juliana was kidnapped in his stead and used as a hostage to force Roberto to deliver himself, but once he had done so, the mercenaries prepared to kill them both. Roberto, Mirage and Karma tried to subdue them, but one of them recovered prematurely and opened fire. Stunned from overtaxing his power, Roberto just stood rooted to the spot; when the mercenary turned his weapon on him, Juliana jumped in front of Roberto and was killed by the bullets she took for him. Mourning her death and determined to avenge her, Roberto joined Professor Xavier in bringing down Pierce and eventually became a founding member of the New Mutants.
Later, Blackheart, of the Hellfire Club, told Bobby that Juliana was supposed to have lived, but someone in Processing messed up. The deal was: Bobby would join the Hellfire Club, and Juliana would get a new start in a recently deceased girl's body. Feeling that he owed his life to Juliana, Bobby had no choice but to accept, and left X-Force to become the third Black Rook.
- 6 appearance(s) of Juliana Sandoval (Earth-616)
- 3 minor appearance(s) of Juliana Sandoval (Earth-616)
- 8 mentions of Juliana Sandoval (Earth-616)
- 2 image(s) of Juliana Sandoval (Earth-616)