UPDATE: As of 10/13/23, it has been confirmed the video shown IS INDEED 100% legit, and is able to run in an emulator. This was shown by the Saturn Homebrew developer XL2, known for his awesome Hellslave project, and his port of Unreal to Saturn:
A hobbyist modder named Frogbull posted a YouTube video Monday that appears to show a homemade prototype of PlayStation exclusive Metal Gear Solid running on the Saturn.
Playable files have not been released to the public as of yet and SHIRO! cannot confirm whether the video is genuine.
“Sadly for the moment I won’t share the ISO to the public,” Frogbull said in a thread they made on SegaXtreme. “I don’t want to see scammers selling it on eBay in a fake Saturn blister [pack].”
When asked in the thread whether a video could be recorded an off-screen video of a real Saturn booting up and running the alleged prototype, Frogbull said that it’s not running on real hardware in the video but rather on an emulator within the RetroArch framework.
“[Of course] I can make a record on Retroarch, open the Shaders, change them in live but even with that with so many people convinced that the Saturn sucks in 3D I’m sure there would still be skeptics,” Frogbull said.
The video shows a Saturn bootup screen followed by logo screens for Metal Gear Solid publisher Konami before a title screen appears, all while original music from the game plays. “New game” is selected, bringing up a difficulty screen. After the player chooses “Hard,” instead of showing the in-game cutscene with credits that are in the original game, this video shows a brief green-tinted Codec conversation screen, complete with the voice of main character Solid Snake:
On the top is the PS1 version of Metal Gear Solid. On the bottom is a screen depicted in Frogbull’s YouTube video. PS1 screengrab is courtesy of World of Longplays’ video. The sprites appear to be smaller in Frogbull’s version and the font is different.
Then it jumps right into gameplay, with Snake moving around the first room of the game. There are no enemies, no radar in the upper-right corner and no credits appearing on top of the gameplay. Some game elements are demonstrated like using cigarettes from the inventory and bringing up the first-person-view binoculars.
On the left is the PS1 version of Metal Gear Solid. On the right is a screen depicted in Frogbull’s YouTube video. PS1 screengrab is courtesy of World of Longplays’ video. Frogbull’s version appears to be zoomed out more than the PS1 version and it lacks a radar and credits appearing on top of the gameplay.
After a little more than a minute, a Codec call rings — prompting the player to press C instead of pressing Select like in the PS1 original — and another green conversation screen appears. But this one quickly turns into a joke, as Sega of Japan mascot Segata Sanshiro appears while his theme song plays. Once the theme ends, so does the video.
On the left is the PS1 version of Metal Gear Solid. On the right is a screen depicted in Frogbull’s YouTube video. PS1 screengrab is courtesy of World of Longplays’ video. Frogbull’s version says “PUSH C” instead of “PUSH SELECT” when the Codec call comes in.
Some established members of the Saturn homebrew development community expressed skepticism at the video and its lack of publicly playable build:
Knight0fDragon, who has worked on the Castlevania Symphony of the Night, Shining Force III, Wachenröder, and many other fan translations and projects.
TrekkiesUnite118, behind the Grandia fan translation, and all around video work with the Saturn.
Ponut64, behind the homebrew Saturn game Side Hop.