Forget about Resident Evil Revelations. This is what you want — a 90 per cent complete version of the never-released Resident Evil for GBC. Until now, it only existed on a couple of carts owned by an anonymous collector but, thanks to a bit of wheeling and dealing, it's now been transformed into a ROM, allowing anyone with a GBC emulator to experience the port of the original PlayStation title.
According to this post on Assemblers, a fundraiser was held to acquire two carts containing the game. Unsurprisingly, the required amount was gathered without much pain and the devices purchased. From the looks of the screenshots, one cart held a play-through with Jill and the other Chris. Both builds are unfinished, buggy and not very challenging. This is probably due, in no small part, to the fact that you have infinite ammunition.
The post mentions Capcom was "not confident that the product would have made both consumers and [it] happy", hence its consignment to the bin of history. Looking at the images, I suppose it does lose something in the translation from 3D to 2D. Resident Evil was praised for its ambience and graphics (which were fantastic for the time) — the gameplay itself was clunky and getting devoured off-screen thanks to the fixed camera angles was a regular occurrence. Even as a die-hard Resi fan, I can understand why Capcom pulled the plug.
Both ROMs are available for download from Assemblers. I'm not going to go into the legalities, but if you want to check them out, there's not a lot stopping you.