It's no longer strange to see elaborate devices built in Minecraft, but this one is particularly eyebrow-raising. Reqaug has built a Minecraft machine that plays Pokemon Fire Red for the Game Boy Advance. It's very rudimentary at the moment (it's missing combat and dialog, among other things), but it's still surprisingly thorough. There's even a level editor and the option to replace textures. As the creator explains, the whole concept revolves around layers of structure blocks (a recent addition) that represent tiles in the game and move when you move.
While there isn't enough here to keep you entertained, Reqaug is quick to stress that his work will "always be in progress." It's more a matter of investing enough time than whether or not a blocky Pokémon recreation is possible. And importantly, this doesn't require modding -- as long as you're using at least Minecraft 1.10, you can try it for yourself. Just don't expect an action game like one of the Super Mario Bros. titles, since Minecraft likely can't draw the virtual screen quickly enough to keep up.