Kyle Hefley worked at 343 games working as a senior designer on the Halo franchise where he worked on armoured super soldiers and alien warriors in Halo 4, Halo 5 and Halo: Infinite. He also worked on the Master Chief design itself in Halo 5. In addition to the Halo series, Hefley has also been known to work on Call of Duty: Black Ops and Sleeping Dogs. Now on his bio at ArtStation, it states that he has now moved on to become lead character artist at Retro Studios.
Unless Retro Studios has a completely unknown project in the works, it’s safe to assume that Hefley will be designing most, if not all, designs for the upcoming Metroid 4. This does beg to questions just how far away Metroid Prime 4 is from release considering character designs are just now going to be underway. But if Metroid fans know anything, it’d be how to be patient.