Plenty of modern games have retro graphics — but how many could actually run on an old console? Retro City Rampage, a throwback to the type of game that you would have found 25 years ago, was recently released on modern consoles, but the project started out as a game that could actually run on the NES. Developer Brian Provinciano's project eventually became too advanced to do so, but he's gone back and tweaked the game to make it run on the NES's limited hardware. The new version is called Rom City Rampage, and though it's largely the same game, Provinciano had to scale down the world to make the game work. Ars Technica details the limitations that Provinciano faced, and you can watch Provinciano's own discussion of the challenge below.