We’ve heard little about the much-anticipated Metroid Prime 4 since it was revealed at E3 two years ago, and now we know why: development isn’t going smoothly. In fact, in a shocking move, Nintendo has announced that it has rebooted the development of the game, essentially starting over from scratch.

“Ever since the announcement, we have not been able to give you an update. Although this is very regrettable, we must let you know that the current development progress has not reached the standards we seek in a sequel to the Metroid Prime series,” explained Nintendo’s senior managing executive officer Shinya Takahashi in a video. “We have determined that the current development status of the game is very challenged, and we had to make a difficult decision as a development team.”

As part of the change, development will be shifting to a new studio, though it was never clear which team was developing the game in the first place. Retro Studios, the team behind the original Prime games, will now handle Prime 4. (Many of the original Prime staff left Retro to form Armature Studios, which released Recore on the Xbox One.)

“We have decided to have the producer, Kensuke Tanabe, work in trust and collaboration with the studio that developed the original Metroid Prime series, Retro Studios in the United States, and restart development from the beginning,” Takahashi explained. “We did not make this decision lightly. This change will essentially mean restarting development from the beginning, so the completion of the game will be delayed from our initial internal plan. We strongly recognize that this delay will come as a disappointment to the many fans who have been looking forward to the launch of Metroid Prime 4.”

Last year at E3, Nintendo of America president Reggie Fils-Aimé said that development on Prime 4 was “progressing well,” though it appears that is no longer the case. In the video, Takahashi promises that the sequel will “stand shoulder to shoulder with the past Metroid Prime series titles” when it is finally complete.