This post is an information dump about Spike/Sky, since I'm quite sure I'm one of the, if not the only person here who knows his canon. XD To find out more about his universe, feel free to poke around
the S.P.D. section on RangerWiki; I wrote a good deal of the content there myself.
Oh, and FYI? The only reason I named him "Spike" was because of his hair. Seriously.
This infodump does contain spoilers for the series. To distinguish between this and ES, I'll just refer to him by his real name, Sky.
Schuyler "Sky" Tate is the son of a veteran Red Ranger and a member of the galactic police force known as Space Patrol Delta (S.P.D.). Sky admired and hero-worshipped his father, who was killed in action when Sky was a young boy. This inspired Sky to join S.P.D. when he grew up, training hard for that day when he would become just like his father- his only desire in life. By the time the series began, he was well on his way- he was in the B-Squad, one step below becoming a Power Ranger, and got promoted to acitve Ranger status when the threat of the evil Emperor Gruumm began to loom.
However, this desire to be like his father actually created problems for him, as it consumed him and caused him to become very arrogant, overconfident in his own abilities, and dismissive of the others. When his commanding officer, Commander Cruger, asked him what he would think if either of his teammates, Bridge Carson or Sydney Drew, were to become the Red Ranger, Sky scoffed at the idea, believing himself to be the only one skilled and worthy enough to lead his squad. This showed Commander Cruger that he was not ready for the task, earning Sky the position of second-in-command as the Blue Ranger. The position of Red instead went to Jack Landors, a former street thief who joined S.P.D. along with fellow thief Elizabeth "Z" Delgado.
For the first part of the series, Sky was a loner. His jealousy of Jack and a feeling that he'd failed prevented him from getting close to his teammates. He began to realize that this attitude didn't work when his disobedience of Jack's orders allowed their enemy, Emperor Gruumm, to steal a valuable resource- diamonds- from Earth in order to power his ships and weapons. Later on, when Sky's "best friend" from before the series began, Dru Harrington, returned to S.P.D. and was revealed to be a turncoat when he tried to assassinate Commander Cruger, Sky learned an important lesson- that his teammates were his true friends.
As the series progressed, Sky still remained professional and somewhat abrasive and strict, but Dru's betrayal on the whole softened his attitude. He continued to learn to relax, loosen up, and treat his teammates as people and friends, not just his colleagues. His initial rivalry with Jack also turned into a friendly one, and the two became very close friends. Aside from Dru's betrayal, the biggest step in Sky's development came toward the end of the series, when Sky accidentally caused Mirloc, the alien criminal who had murdered his father, to escape. He nearly quit being a Ranger in shame, but was pushed by Jack into tracking Mirloc down. Mirloc attempted to break Sky's confidence, but he accepted Jack's morpher and brought in his father's murderer as the Red Ranger. Afterward, Sky realized that he was proud to be the Blue Ranger and that he didn't have to be Red to be someone his father would be proud of.
Sky continued to mature and progress, taking a secondary leadership role whenever Jack was absent for some reason. At the end of the series, after the defeat of Emperor Gruumm, Jack decided to leave S.P.D. When Sky told Commander Cruger that he'd follow anyone into battle whom Cruger felt worthy of wearing the color red, he was promoted to the position of Red Ranger and team leader. It is at this point where I take him from his canon. He is much more relaxed and sociable than he was for most of the series, but can still be abrasive, sulky and wanting to be by himself when he's scared or in a bad mood.
Though of course he doesn't know it yet in Edensphere, Sky is a mutant. He has the genetic power to create force fields with his mind. He makes the shields by waving his arms in a wide circle. They are apparently painful to the touch and have been shown in canon to repel explosions and laser fire, though they can be shattered by a powerful enough blast. His powers were the result of a freak accident before he was born while his father (and possibly his mother) worked as a scientist at S.P.D. on an experiment involving prolonged exposure to cellular enhancers. This altered their childrens' DNA- all of the S.P.D. B-Squad Rangers have a unique power.
Physically, Sky is very tall and physically fit, though he never uses his size to intimidate or bully. He has a strong sense of justice and is also obedient to any authority figures he sees.