The D-Reaper’s simple red gelatinous form belies its true deadly nature, as a nigh-unstoppable force existing only to destroy. The matter that forms it is apparently capable of indefinite replication, enabling it to spread and cover massive areas. From this mass it can shape Agents – separate beings which are all controlled by the D-Reaper’s single consciousness, connected to it by a life cord. An ever-changing being, it evolves itself, altering it’s form and capabilities, through the study of other forms of life.
The D-Reaper began its “life” in 1970, as a program known as “the reaper,” created by the American Department of Defence to delete excess data and manage the growth of artificial intelligence. The reaper’s first job was to delete “the worm,” the very first computer virus. In the 80's, the reaper was used as the basis for the security system of “Project Echelon,” a worldwide communications interception network created by the US government to secretly monitor private information. Note that all this information is real and allegedly happened in the real world. The US government denies that Project Echelon even exists, but other countries that are a part of the project have come forward and admitted to its use.
In 1990, the reaper attacked the fledgling Digital World, which had recently become populated by the digital life forms created by the Monster Makers – theDigimon. It was the reaper’s job to control artificial intelligence, and so it set about deleting Digimon – but as it did so, it absorbed their data, and it began to mutate as a result. It buried itself away, beneath the Digital World, and slumbered as it transformed, into a being of sentience and great power.
In the year 200X, the reaper emerged again, awakened by the sheer amount of excess data that had been caused by Digivolving and the growth of the Digital World during it’s period of inactivity. Now it was the D-Reaper, and it set out to destroy all forms of life that it saw as having transgressed their boundaries – a deadly interpretation of it’s original programming - and Digimon were its first target. The four Digimon Sovereign attempted to quell it by abandoning Digivolving, trying to prove that they would not evolve to a threatening level of power, but this meant nothing to the D-Reaper.
When the Digimon Tamers came to the Digital World, they encountered the Sovereigns, who explained to them of their “true enemy” – it was Shibumi who was able to tell the Tamers that D-Reaper was it’s name. Even as this happened, Baihumon was engaged in battle with the D-Reaper, which then left to seek out Calumon, the source of Digivolving power. As the Tamers came to his rescue, Sakuyamon fended off the D-Reaper’s chaos for a short time, but it soon burst forth in a gusher, as a small portion of it possessed Jeri’s puppet, and lured her away from the other Tamers. The D-Reaper was able to capture her, and created the Jeri Type agent to take her place amongst the Tamers while it studied Jeri to learn more about humans. As the Tamers tried to leave the Digital World in an ark created by the Monster Makers, the D-Reaper attacked the Hypnos central processor, almost preventing the kids from escaping. However, the Monster Makers were able to corral the processing power of computers all across the world to finish their calculations and bring the kids home.
However, the escape was ultimately futile, as the D-Reaper’s chaos followed them back to Earth through the Hypnos system, and immediately began to spread overShinjuku, keeping the Kernel Sphere – the core of it’s consciousness – high between the two towers of the Hypnos building, with Jeri sealed inside. As it continued it’s spread on Earth, so too did it continue its destruction of the Digital World, with the Sovereigns unable to defeat it.
Attacks from the military and the Tamers were repeatedly fended off by the D-Reaper’s Agents, but Calumon and Beelzemon were able to get inside the Kernel Sphere to try and save Jeri, only to wind up trapped themselves, as the D-Reaper continued to spread, increasing it’s strength and power by amplifying and feeding off of Jeri’s negative energy. As the battles continued, the D-Reaper mass appeared in countries all across the globe, growing and spreading there, too. After the Global Taskforce dropped magnetic probes into the D-Reaper’s mass, and it destroyed the majority of them with it’s own heat, it had absorbed enough energy from Jeri, and evolved itself again, assuming the form of the Mother D-Reaper.
A week later, the Tamers and their Digimon rallied and initiated their final attack on the D-Reaper, battling against armies of Agents within the its mass, as the D-Reapers from all across the world began to combine together, as the portal between the worlds was opened. The Monster Makers had deduced that the interior of the D-Reaper was a quantum bubble, where positive and negative forces were perfectly in balance, and had put the Juggernaut program inside of Terriermon, which would act like a miniature big bang, disrupting the D-Reaper's balanced structure. When the Digimon Sovereign removed the Cable Reaper from the fight,MegaGargomon flew into the portal and used the Juggernaut to create a vortex which sucked the D-Reaper back into the Digital World, and devolved it back into it’s original, harmless state. Shibumi first mentions the Digimon Sovereigns’ mystery opponent in “Shibumi Speaks.” It first appears in “Azulongmon Explains It All,” in the form of a few simple chaos bubbles, where it's name and origins are also first revealed. It's voice is supplied by Bridgette Hoffman.