In Guilmon's entry, I briefly touched on the fact that the main digimon(Rookie form) that WiZ (leaders of the Digimon project) suggested was, in fact, Impmon.
As soon as you see him, you can tell that he's a bratty, wise-cracking type, and it was a definitely a departure from the heroes from the previous seasons of Digimon.
However, as I wrote earlier, I wanted to begin the story with the main digimon as innocent and pure as possible. I voiced my dissent, and the next digimon to be nominated was Guilmon.
According to WiZ's plans for Digimon, Impmon was going to be one of the main enemies until the midpoint of the series. After Digimon Tamers was broadcast, a game called "Digimon Medley" was released for the Wonderswan console, and this game reflects this original plan. (One of the Sovereigns, Ebonwumon, appears as the final enemy in this game.)
All of this serves to illustrate how powerfully Impmon was to affect the storyline. However, I felt from the beginning that we could not release Impmon's full potential and attractive charm as an enemy that is powerful from the start.
Some of the early main visuals (advertising posters, etc) make Impmon appear to be a sinister, demonic, powerful figure, but as you can see from the series, we did not take this route.
Impmon is a digimon who wants to become powerful. This is a natural urge in a digimon. However, Impmon is still childish in many ways, and he did not have a happy relationship with his partners. The strength that Impmon longs for is, as a result, a very dangerous thing.
In order to digivolve into his Ultimate form, the powerful Beelzemon, Impmon makes a "deal with the devil", symbolically selling his soul to the Deva. The plotline that I thought up for Impmon, leading up to the midpoint of the series, was as above.
Mr. Motoki Yoshimura wrote the first episode that Impmon appears in. Mr. Yoshimura has a great deal of experience writing such villains as Puppetmon, and he gave Impmon his sarcastic, acerbic, yet not-entirely-unloveable voice.
Everything after that-- particularly the relationship between Impmon and his two young partners, his agreement with the Deva, his digivolution, his depression, and finally his digivolution to Blast Mode in a desperate attempt to save Jeri -- these were all penned by Mr. Maekawa. Many of these episodes were also directed by Mr. Maekawa and Mr. Shibata.
At first, it was sheer coincidence that Mr. Maekawa was in charge of so many episodes featuring Impmon. But after the mid-point of the series, both Mr. Maekawa and myself were cognizant of what was happening, and adjusted the script-writing rotation and series direction so that we could have Mr. Maekawa writing Impmon.
Mr. Hiroki Takahashi was cast for the role of Impmon in the Japanese version. Since Impmon would eventually digivolve into Beelzemon, we decided that we should have a male actor from the start. Just as we had hoped, Mr. Takahashi played both Impmon and Beelzemon with great skill.