- Some folk at Retro Studios wanted to develop a new ip that involved 3rd person sci-fi action with intense aerial combat.

- Others apparently were leaning towards taking the Star Fox helm.

- Nintendo sees Retro Studios as a very competent developer and worked with them in creating the hybrid title of Star Fox – Metroid: Fusion Saga.

- The title has multiple gameplay mechanics and needed a wide staff of talent to incorporate the many ideas.

- The story begins as you control Fox McCloud and the Star Fox team on deep space mission in your Arwing, flying through a Meteos-like stage. As you enter a light speed warp, there’s a collision with an orange ship (Samus’) and the game continues with you now plummeting to a planet as Samus in her craft. You’re in mild control of her ship, using the Wii U controller to look around and touch screen press the lit up buttons to prepare for impact (while the TV stays locked on what you see out of the cockpit). You’re now on land, as a “yet again” stripped down Samus Aran with the most basic of weapon abilities, in first person perspective, traversing through this unknown planet
.
- The game switches off between intense Arwing space and planetary battles as Fox makes his way to the planet that Samus crashed on and a Metroid Prime-like experience of gameplay as Samus on this planet, gradually uncovering its mysteries, leveling up, etc.

- The Star Fox stages represent what the series is best known for, including the chatter and coming to the aid of the rest of your team, all range mode battles, and on rails stages.

- The Metroid part of the game puts you alone, void of human or any talking character contact, and like the Prime series, sees you gaining upgrades, battling bosses, and in this case, repairing your ship.

- The game is said to be epic in size, scope, ambition.

- The pacing has been perfected to not interrupt what the feeling is behind either franchise, since Star Fox is more often known for being acceptable to have short sessions with and Metroid rather the opposite. You can opt to continue playing either just Samus’ part or Fox’s part without crossing over for much of the main game (or play it as it’s scripted back and forth), but will eventually have to complete both, as the characters will ultimately meet up.

- There will be later parts in the game where you do get to control Samus’ ship and fly it Star Fox style.

- Likewise, Fox McCloud will be controllable by foot (both the above and this bullet point represent a period in the game after the two sides meet up) and be played via 3rd person perspective. Think of Jet Force Gemini with Fox’s known agility as he’s portrayed to having in the Smash Bros. series. (Fox will move more like Ryu Hayabusa from Ninja Gaiden and less like he did in Star Fox Adventures).

- Though a tentative title, the idea behind the story of “Fusion Saga” is both a play on the fact that the two series are fusing together into one game and of course, a storyline behind Andross using Metroids to enhance himself, his army, etc.

- Star Fox – Metroid: Fusion Saga is wholly a satisfying adventure game as Samus, an equally electrifying aerial combat game as Fox, and something that delivers an exciting, special change that fans will love.

- In consideration was the Star Fox portion having 4 player co-op online, but instead the game will have leaderboards for time and percent complete for all parts of the game and multiplayer will be simply versus mode based.

I've got my doubts about this, but it would be very interesting if true. Of course, the source link says as well that it's very possible this never got past the concept stage even if it is real, so I'm not counting on it.

Fake or not, still interesting concept nonetheless. Even if it never sees the light of day or whatever, it's still fun to read and fun to think about such a possible crossover.

What we need is a Pokémon - Metroid crossover. I need to know what comes of Pikachu and Samus' relationship!

Lieutenant Surge is American, dude. I'm sure he's seen plenty of non-crossover wars.

Considering the sign outside his gym refers to him as "The Lightning American," I would presume so.

Sounds pretty interesting, but something feels so...off... about this concept
like a really weird fanfiction or something.... though if it did come to fruition, I'd definitely check it out.