Metroid Prime: Federation Force might suggest Metroid Prime 4

Nintendo has finally released the highly unanticipated new Metroid Prime game, Federation Force. The game has been met with mixed reviews with scores ranging from 4/10 to 9/10. Prior to the game's release, Nintendo opened up on the game, saying that a negative reaction was expected, however, they believed that playing the game would change people's minds.

Unfortunately, a majority of fans wanted a "true Metroid game" and petitioned the release of Federation Force. While fans have been groaning about Federation Force, it appears as though something in the end credits of the game suggests a future for the Metroid Prime series.

According to Eurogamer, post-credit scene after Federation Force's credits shows a Metroid egg "being hacked and stolen" from the Galactic Federation. Who steals the egg is unknown, but fans believe it was Sylux from Metroid Prime Hunters.

A story between Sylux and Samus has been suggested before by the Metroid Prime series boss Kensuke Tanabe. 

"Personally, I'd like to create a story centering around Sylux and Samus," Tanabe told Eurogamer. "We've done a story based on the Hunters, and this time around we're doing a story on the Galactic Federation. I would like to cross the two over in the future. And of course, see a little more of Samus."

Tanabe does mention crossing the two games over, so it's unclear if a future game would feature Sylux and Samus with Federation Force gameplay. If a proper Metroid game were to ever come to fruition, it would likely be on the NX.