Independent journalist Liam Robertson reported way back in 2015 that developer Retro Studios originally had an idea to include fully playable Super Metroid inside of GameCube first-person shooter Metroid Prime, but Nintendo shot it down. Robertson had to keep his source anonymous at the time, but now we have direct confirmation at last that this reporting was accurate. Former Metroid Prime developer David Kirsch, also known as Zoid, stated it outright in an interview with Kiwi Talkz.
When Kirsch joined Retro Studios, he was supposed to work on a project called Thunder Rally, but that was eventually canceled and he ended up on Metroid Prime. He hadn’t played Super Metroid, so he decided to play it for the sake of better understanding his current project. He ended up loving it and said he played through it twice in about three days. That may have been what spurred the idea to include Super Metroid in Metroid Prime.
“I ported a SNES emulator to the GameCube and had (it) actually running, just for fun,” said Kirsch, and he asked Retro if they could actually include Super Metroid in Metroid Prime. Retro then asked Nintendo, but Nintendo vetoed it because it wasn’t willing to use third-party emulation software in its games. However, Nintendo did have a NES emulator handy for GameCube, so this scenario ultimately paved the way for the original Metroid to be accessible through the link cable with Metroid Fusion on Game Boy Advance.