First Appearance: Wars Are Won By Those Who Dare: Reunions
Sparks was the first child born onboard the Olympian Fury about seven months after it survived the Plutarkian attack. He and his mother Stella became minor celebrities in Olympian City because of it. Yet Stella and her friend Roddie managed to give him a normal childhood. He didn't look much like his mother other than sharing her hair. Stella would (with a sad humor) tell people that Sparks had gotten her brains and his father's brawn and looks. Other than that, she was curiously silent about the Freedom Fighter that had been left behind on Mars.
Sparks was stronger and smarter than kids his own age. By age three, he had the reading level of a second grader, starting to figure out English, and was as strong as a six-year-old. But it didn't prepare him for his mother growing sick and leaving him. Roddie took him in and had to tell the young boy that his father was dead as well. For the next four years, it was just him and Roddie. Roddie was still the second-in-command of the Fury. Sparks started school and quickly accelerated through several grades. But he couldn't manage to let anti-alien remarks about Roddie slide. He often got into fights, holding his physical own with students bigger and older than he was.
The Captain of the Fury died and Roddie was promoted to command of the entire ship. Colonel Exhaust took command of the Internal Security forces after their former commander died under suspicious circumstance. Anti-alien hostility began to increase. Sparks didn't miss the skirmishes between Roddie and Colonel Exhaust, and how Exhaust would kill her if he could find a way. He made a deal with the mercenary Tala. She gave him a gun for a copy of the Olympian Fury's plans. He was prepared for anything Exhaust might try. And completely missed when Roddie and Lance started dating. Before he could decide if Lance was trustworthy, Roddie goes ahead and married him!
Lance proved that he was worthy of trust and Sparks slowly warmed up to him. But he didn't have any right to tell him what to do, which to give the Captain of the Rock Squad credit he learned quickly. Things began to settle into a routine--even the constant vigilance for a move from Colonel Exhaust. Then a Plutarkian ship was captured and they salvaged a transport booth from it.
A week later, a trio of Freedom Fighters and a human woman transported to the Fury through it. They turned out to be Roddie's cousin Throttle and his friends Modo and Vinnie. Roddie had heard that they had died around the same time as Sparks's mother and father, but they had made their way to Earth and helped their friend Charley Davidson battle the Plutarkians there. They arrived the same day of Roddie's Captain's Ball and the day Sparks got himself expelled from school. Roddie forbid him to go to the ball but he sneaked in to watch her back, running into Modo. Something about the big mouse made Sparks trust him. He left Roddie under Modo's protection and got back to the apartment before Lance and Roddie.
His first day of punishment work duties was uneventful up until he went looking for Modo. He found the biker mouse in the Hall of Memories. And that's where an Internal Security officer found him. Modo took care of that creep and they escaped to find a coup had started. They rescued Axle and met up with Tala and Vinnie. From Tala's ship, they struck back at Colonel Exhaust's forces. Sparks freed Roddie and Throttle from the Internal Security cells, but Roddie sent him home with Modo after an Internal Security officer used him as a hostage to blow up the elevator to the bridge.
The Biker Mice included Sparks in on their post-victory celebration until it came to a screeching halt with Charley's collapse. And then came to a further halt with the revelation that Modo is Sparks's long-lost father. Modo and Roddie started fighting over him and Sparks ran. Modo found him at Stella's place in the Hall of Memories. Sparks found comfort in his father's arms and Stella's wish came true, Sparks has a father in his life. When the Biker Mice and Charley left the Fury, Sparks went with them back to Chicago (read Wars Are Won By Those Who Dare: Reunions). The question is Chicago ready for an eight-year-old, Martian mouse?
Michaelangelo calls Sparks "J'onn Jonzz" the real identity of the Martian Manhunter (read Wars Are Won By Those Who Dare: Family, Friends, and Foes).
Sparks realized that Turbo must have had a Martian A.I. bike in order to attack Charley, and rescued the bike from the wrecked spaceship in the Quigley Field scoreboard. The bike resembles Throttle's only with a dull metallic gold crankcase and black leather seat. It bonded with him and he named it Cavalry.