In the recent past of three thousand years from now, a rabbit named Jazz Jackrabbit braved the perils of the galaxy in a never ceasing search for the rabbit princess, Eva Earlong. After many brave adventures, Jazz finally recovered the princess from her kidnapper, Devan Shell, and returned Eva to her home planet of Carrotus. By this time, the two rabbits had fallen in love, and arrangements had been made for their marriage. Unfortunately, as the cliché goes, it's darn hard to keep a criminally insane turtle down for long. Mere days after his shocking defeat at the hands of Jazz Jackrabbit, and the subsequent crashing of all his plans for galactic domination, Devan Shell had concocted a new, simpler plan.
The galaxy was a really big place, so it was only logical to start with just one planet. Thus, Devan decided to conquer Carrotus, the home of the rabbits, the ancient enemies of the turtles. The only obstacle was, of course, the rabbits. Devan began work upon a machine that would remove this one last obstacle. This machine, dubbed the Junction Jumper 2000 (or JJ2 for short), was, on the eve of Jazz and Eva's wedding, all ready save for one small detail - the power source.
The derelict planet of Tubelectric could easily have powered JJ2, and hundreds of other contraptions like it, but JJ2 was compact and needed a small source of power, about the size of Devan himself. A power gem, maybe.
Power gems were a recognized phenomenon in the galaxy. Properly faceted gemstones, when bombarded with positively charged photons, would begin glowing with a radiance possibly derived from some parallel universe. This radiance was not so much normal light as pure unchecked energy, and could easily be harnessed to provide enough electric energy to run machines up to ten times the size of the gem itself, even subtracting the energy needed to continue the photon bombardment.
The most popular source for power gems was the rich grassland planet of Diamondus, where for some unknown reason, power gems seemed almost to grow out of the dirt. Sadly, after Devan's brief takeover of the planet during his initial attempt at galactic domination, the Galactic Rabbits had banished Diamondus to a pocket dimension which only the most highly trained lagomorphic personnel could enter. Devan had no way of getting into the Diamondus Dimension, but thanks to his excessively elaborate spy network, he did know where an as of yet untapped power gem could be found.