Fans of Kid Icarus had to endure a long and painful wait between the original NES and Game Boy titles and the eventual 3DS update, but had Star Wars: Rogue Squadron studio Factor 5 had its way, we would have been playing a sequel a little bit sooner.

Unseen 64 staffer and occasional Nintendo Life contributor Liam Robertson has published an in-depth video which looks at the history of Factor 5's unreleased Kid Icarus pitch. The studio became involved with the project off the back of its work on the aforementioned Nintendo exclusive Rogue Squadron franchise, and early concept art reveals a much darker and more mature tone than previous titles in the series.

As if to reflect this new direction, the project was referred to internally as "Icarus", and one of the possible storylines involved Pit's banishment from Sky World for some unspecified crime. The resultant game would ultimately be a quest of redemption, with different concept drawings showing Pit with black wings, a sinister tattoo and a blackened, infected arm.

According to the developers that Robertson spoke to, the game would have made good use of Factor 5's experience with 3D flight. Pit wouldn't have been limited to hovering and would be able to take to the skies in order to engage and battle with enemies. The game engine was based on the one created for the PS3 exclusive Lair, and would have offered 60fps performance.

Alas, it wasn't meant to be. Early in development Nintendo submitted a character model to Factor 5 which was basically Pit as he appeared in Super Smash Bros. Brawl. The idea was that Factor 5 could include this model in their playable prototype, but they chose to ignore it and create their own more mature representation of the character. Shortly after this point the project began to fall apart.

The prototype was pitched to NCL, which rejected it as too extreme a deviation from the core ideals of the franchise. Former Factor 5 staffer Joe Spataro feels that this could have been the straw that broke the camel's back:

With Icarus, I feel like we were missing the point. Nintendo sent us the model of Kid Icarus, very much like the one that appears in Smash Bros., but we didn't use it. We made our own version. It was more mature, maybe even a little dark. It felt more like Devil May Cry. I knew Nintendo would never go for the adult version of Pit. In fact, I'd wager they took it as an insult that we didn't use their version.

Factor 5 would abandon work on Icarus and all that remains is a handful of character models and test animations, some of which are shown in Robertson's video below. Nintendo would famously enlist Masahiro Sakurai to create a true successor, with Kid Icarus: Uprising launching on the 3DS in 2012.